diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 9e65f520..dcb78521 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -22,10 +22,10 @@ jobs:
             args: "--target x86_64-apple-darwin"
             python-version: "3.12"
             backend: "pytorch"
-          # - platform: 'ubuntu-22.04'
-          #   args: ''
-          #   python-version: '3.12'
-          #   backend: 'pytorch'
+          - platform: "ubuntu-22.04"
+            args: ""
+            python-version: "3.12"
+            backend: "pytorch"
           - platform: "windows-latest"
             args: ""
             python-version: "3.12"
diff --git a/backend/backends/pytorch_backend.py b/backend/backends/pytorch_backend.py
index 8059dc09..729053b4 100644
--- a/backend/backends/pytorch_backend.py
+++ b/backend/backends/pytorch_backend.py
@@ -374,6 +374,7 @@ def _generate_sync():
     "small": "openai/whisper-small",
     "medium": "openai/whisper-medium",
     "large": "openai/whisper-large-v3",
+    "turbo": "openai/whisper-large-v3-turbo",
 }
 
 
@@ -591,21 +592,20 @@ def _transcribe_sync():
             )
             inputs = inputs.to(self.device)
             
-            # Set language if provided
-            forced_decoder_ids = None
+            # Generate transcription
+            # If language is provided, force it; otherwise let Whisper auto-detect
+            generate_kwargs = {}
             if language:
-                # Support all languages from frontend: en, zh, ja, ko, de, fr, ru, pt, es, it
-                # Whisper supports these and many more
                 forced_decoder_ids = self.processor.get_decoder_prompt_ids(
                     language=language,
                     task="transcribe",
                 )
+                generate_kwargs["forced_decoder_ids"] = forced_decoder_ids
             
-            # Generate transcription
             with torch.no_grad():
                 predicted_ids = self.model.generate(
                     inputs["input_features"],
-                    forced_decoder_ids=forced_decoder_ids,
+                    **generate_kwargs,
                 )
             
             # Decode
diff --git a/backend/main.py b/backend/main.py
index 3d2ec359..04c9190f 100644
--- a/backend/main.py
+++ b/backend/main.py
@@ -14,7 +14,6 @@
 import asyncio
 import uvicorn
 import argparse
-import torch
 import tempfile
 import io
 from pathlib import Path
@@ -22,6 +21,18 @@
 import asyncio
 import signal
 import os
+
+# Set HSA_OVERRIDE_GFX_VERSION for AMD GPUs that aren't officially listed in ROCm
+# (e.g., RX 6600 is gfx1032 which maps to gfx1030 target)
+# This must be set BEFORE any torch.cuda calls
+if not os.environ.get("HSA_OVERRIDE_GFX_VERSION"):
+    os.environ["HSA_OVERRIDE_GFX_VERSION"] = "10.3.0"
+
+# Suppress noisy MIOpen workspace warnings on AMD GPUs
+if not os.environ.get("MIOPEN_LOG_LEVEL"):
+    os.environ["MIOPEN_LOG_LEVEL"] = "4"
+
+import torch
 from urllib.parse import quote
 
 
@@ -1022,11 +1033,12 @@ async def transcribe_audio(
         # Transcribe
         whisper_model = transcribe.get_whisper_model()
 
-        # Check if Whisper model is downloaded (uses default size "base")
+        # Check if Whisper model is downloaded
         model_size = whisper_model.model_size
-        # Map model sizes to HF repo IDs (whisper-large needs -v3 suffix)
+        # Map model sizes to HF repo IDs (some need special suffixes)
         whisper_hf_repos = {
             "large": "openai/whisper-large-v3",
+            "turbo": "openai/whisper-large-v3-turbo",
         }
         model_name = whisper_hf_repos.get(model_size, f"openai/whisper-{model_size}")
 
@@ -1490,6 +1502,13 @@ def check_chatterbox_loaded():
             "model_size": "large",
             "check_loaded": lambda: check_whisper_loaded("large"),
         },
+        {
+            "model_name": "whisper-turbo",
+            "display_name": "Whisper Turbo",
+            "hf_repo_id": "openai/whisper-large-v3-turbo",
+            "model_size": "turbo",
+            "check_loaded": lambda: check_whisper_loaded("turbo"),
+        },
     ]
     
     # Build a mapping of model_name -> hf_repo_id so we can check if shared repos are downloading
@@ -1684,6 +1703,10 @@ async def trigger_model_download(request: models.ModelDownloadRequest):
             "model_size": "large",
             "load_func": lambda: transcribe.get_whisper_model().load_model("large"),
         },
+        "whisper-turbo": {
+            "model_size": "turbo",
+            "load_func": lambda: transcribe.get_whisper_model().load_model("turbo"),
+        },
     }
     
     if request.model_name not in model_configs:
@@ -1810,6 +1833,11 @@ async def delete_model(model_name: str):
             "model_size": "large",
             "model_type": "whisper",
         },
+        "whisper-turbo": {
+            "hf_repo_id": "openai/whisper-large-v3-turbo",
+            "model_size": "turbo",
+            "model_type": "whisper",
+        },
     }
 
     if model_name not in model_configs:
@@ -2044,7 +2072,12 @@ def _get_gpu_status() -> str:
     """Get GPU availability status."""
     backend_type = get_backend_type()
     if torch.cuda.is_available():
-        return f"CUDA ({torch.cuda.get_device_name(0)})"
+        device_name = torch.cuda.get_device_name(0)
+        # Check if this is ROCm (AMD) or CUDA (NVIDIA)
+        is_rocm = hasattr(torch.version, 'hip') and torch.version.hip is not None
+        if is_rocm:
+            return f"ROCm ({device_name})"
+        return f"CUDA ({device_name})"
     elif hasattr(torch.backends, 'mps') and torch.backends.mps.is_available():
         return "MPS (Apple Silicon)"
     elif backend_type == "mlx":
diff --git a/tauri/src-tauri/src/audio_capture/linux.rs b/tauri/src-tauri/src/audio_capture/linux.rs
index 8af26e97..3cae59e9 100644
--- a/tauri/src-tauri/src/audio_capture/linux.rs
+++ b/tauri/src-tauri/src/audio_capture/linux.rs
@@ -1,16 +1,312 @@
 use crate::audio_capture::AudioCaptureState;
+use base64::{engine::general_purpose, Engine as _};
+use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
+use cpal::{SampleFormat, StreamConfig};
+use hound::{WavSpec, WavWriter};
+use std::io::Cursor;
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
+use std::thread;
 
+/// Start capturing system audio on Linux using PulseAudio monitor sources.
+///
+/// PulseAudio exposes "monitor" devices that mirror the output of each sink,
+/// allowing us to capture whatever audio is currently playing on the system.
+/// We use `cpal` with the default host (which will be PulseAudio or PipeWire
+/// on modern Linux) and look for monitor input devices.
 pub async fn start_capture(
     state: &AudioCaptureState,
     max_duration_secs: u32,
 ) -> Result<(), String> {
-    todo!("implement Linux audio capture")
+    // Reset previous samples
+    state.reset();
+
+    let samples = state.samples.clone();
+    let sample_rate_arc = state.sample_rate.clone();
+    let channels_arc = state.channels.clone();
+    let stop_tx = state.stop_tx.clone();
+    let error_arc = state.error.clone();
+
+    // Use AtomicBool for stop signal (works across threads)
+    let stop_flag = Arc::new(AtomicBool::new(false));
+    let stop_flag_clone = stop_flag.clone();
+
+    // Create tokio channel and spawn a task to bridge it to the AtomicBool
+    let (tx, mut rx) = tokio::sync::mpsc::channel::<()>(1);
+    *stop_tx.lock().unwrap() = Some(tx);
+
+    tokio::spawn(async move {
+        rx.recv().await;
+        stop_flag_clone.store(true, Ordering::Relaxed);
+    });
+
+    // Spawn capture on a dedicated thread
+    thread::spawn(move || {
+        let host = cpal::default_host();
+
+        // Try to find a monitor device for system audio capture.
+        // On PulseAudio/PipeWire, monitor sources have "monitor" in their name.
+        let device = {
+            let mut monitor_device = None;
+
+            if let Ok(devices) = host.input_devices() {
+                for d in devices {
+                    if let Ok(name) = d.name() {
+                        let name_lower = name.to_lowercase();
+                        if name_lower.contains("monitor") {
+                            eprintln!("Linux audio capture: Found monitor device: {}", name);
+                            monitor_device = Some(d);
+                            break;
+                        }
+                    }
+                }
+            }
+
+            match monitor_device {
+                Some(d) => d,
+                None => {
+                    // Fallback to default input device (microphone)
+                    eprintln!("Linux audio capture: No monitor device found, falling back to default input");
+                    match host.default_input_device() {
+                        Some(d) => d,
+                        None => {
+                            let error_msg = "No audio input device available".to_string();
+                            eprintln!("{}", error_msg);
+                            *error_arc.lock().unwrap() = Some(error_msg);
+                            return;
+                        }
+                    }
+                }
+            }
+        };
+
+        let device_name = device.name().unwrap_or_else(|_| "unknown".to_string());
+        eprintln!("Linux audio capture: Using device: {}", device_name);
+
+        // Get supported config
+        let config = match device.default_input_config() {
+            Ok(c) => c,
+            Err(e) => {
+                let error_msg = format!("Failed to get default input config: {}", e);
+                eprintln!("{}", error_msg);
+                *error_arc.lock().unwrap() = Some(error_msg);
+                return;
+            }
+        };
+
+        let sample_rate = config.sample_rate().0;
+        let channels = config.channels();
+        let sample_format = config.sample_format();
+
+        eprintln!(
+            "Linux audio capture: Config - {}Hz, {} channels, format: {:?}",
+            sample_rate, channels, sample_format
+        );
+
+        *sample_rate_arc.lock().unwrap() = sample_rate;
+        *channels_arc.lock().unwrap() = channels;
+
+        let stream_config = StreamConfig {
+            channels,
+            sample_rate: cpal::SampleRate(sample_rate),
+            buffer_size: cpal::BufferSize::Default,
+        };
+
+        let samples_clone = samples.clone();
+        let error_arc_clone = error_arc.clone();
+        let stop_flag_for_stream = stop_flag.clone();
+
+        let err_fn = {
+            let error_arc = error_arc.clone();
+            move |err: cpal::StreamError| {
+                let error_msg = format!("Stream error: {}", err);
+                eprintln!("{}", error_msg);
+                *error_arc.lock().unwrap() = Some(error_msg);
+            }
+        };
+
+        let stream = match sample_format {
+            SampleFormat::F32 => {
+                let samples = samples_clone.clone();
+                let stop = stop_flag_for_stream.clone();
+                device.build_input_stream(
+                    &stream_config,
+                    move |data: &[f32], _: &cpal::InputCallbackInfo| {
+                        if stop.load(Ordering::Relaxed) {
+                            return;
+                        }
+                        let mut guard = samples.lock().unwrap();
+                        guard.extend_from_slice(data);
+                    },
+                    err_fn,
+                    None,
+                )
+            }
+            SampleFormat::I16 => {
+                let samples = samples_clone.clone();
+                let stop = stop_flag_for_stream.clone();
+                device.build_input_stream(
+                    &stream_config,
+                    move |data: &[i16], _: &cpal::InputCallbackInfo| {
+                        if stop.load(Ordering::Relaxed) {
+                            return;
+                        }
+                        let mut guard = samples.lock().unwrap();
+                        for &s in data {
+                            guard.push(s as f32 / 32768.0);
+                        }
+                    },
+                    err_fn,
+                    None,
+                )
+            }
+            SampleFormat::U16 => {
+                let samples = samples_clone.clone();
+                let stop = stop_flag_for_stream.clone();
+                device.build_input_stream(
+                    &stream_config,
+                    move |data: &[u16], _: &cpal::InputCallbackInfo| {
+                        if stop.load(Ordering::Relaxed) {
+                            return;
+                        }
+                        let mut guard = samples.lock().unwrap();
+                        for &s in data {
+                            guard.push((s as f32 / 32768.0) - 1.0);
+                        }
+                    },
+                    err_fn,
+                    None,
+                )
+            }
+            _ => {
+                let error_msg = format!("Unsupported sample format: {:?}", sample_format);
+                eprintln!("{}", error_msg);
+                *error_arc_clone.lock().unwrap() = Some(error_msg);
+                return;
+            }
+        };
+
+        let stream = match stream {
+            Ok(s) => s,
+            Err(e) => {
+                let error_msg = format!("Failed to build input stream: {}", e);
+                eprintln!("{}", error_msg);
+                *error_arc_clone.lock().unwrap() = Some(error_msg);
+                return;
+            }
+        };
+
+        if let Err(e) = stream.play() {
+            let error_msg = format!("Failed to start stream: {}", e);
+            eprintln!("{}", error_msg);
+            *error_arc_clone.lock().unwrap() = Some(error_msg);
+            return;
+        }
+
+        eprintln!("Linux audio capture: Stream started successfully");
+
+        // Keep thread alive until stop signal
+        loop {
+            if stop_flag.load(Ordering::Relaxed) {
+                break;
+            }
+            std::thread::sleep(std::time::Duration::from_millis(100));
+        }
+
+        // Stream will be dropped here, stopping capture
+        eprintln!("Linux audio capture: Stream stopped");
+    });
+
+    // Spawn timeout task
+    let stop_tx_clone = state.stop_tx.clone();
+    tokio::spawn(async move {
+        tokio::time::sleep(tokio::time::Duration::from_secs(max_duration_secs as u64)).await;
+        let tx = stop_tx_clone.lock().unwrap().take();
+        if let Some(tx) = tx {
+            let _ = tx.send(()).await;
+        }
+    });
+
+    Ok(())
 }
 
 pub async fn stop_capture(state: &AudioCaptureState) -> Result<String, String> {
-    todo!("implement Linux audio capture stop")
+    // Signal stop
+    if let Some(tx) = state.stop_tx.lock().unwrap().take() {
+        let _ = tx.send(());
+    }
+
+    // Wait a bit for capture to stop
+    tokio::time::sleep(tokio::time::Duration::from_millis(500)).await;
+
+    // Check if there was an error during capture
+    if let Some(error) = state.error.lock().unwrap().as_ref() {
+        return Err(error.clone());
+    }
+
+    // Get samples
+    let samples = state.samples.lock().unwrap().clone();
+    let sample_rate = *state.sample_rate.lock().unwrap();
+    let channels = *state.channels.lock().unwrap();
+
+    if samples.is_empty() {
+        return Err(
+            "No audio samples captured. Make sure audio is playing on your system during recording."
+                .to_string(),
+        );
+    }
+
+    // Convert to WAV
+    let wav_data = samples_to_wav(&samples, sample_rate, channels)?;
+
+    // Encode to base64
+    let base64_data = general_purpose::STANDARD.encode(&wav_data);
+
+    Ok(base64_data)
 }
 
 pub fn is_supported() -> bool {
-    false
+    // Check if we can find a monitor device for system audio capture
+    let host = cpal::default_host();
+    if let Ok(devices) = host.input_devices() {
+        for d in devices {
+            if let Ok(name) = d.name() {
+                if name.to_lowercase().contains("monitor") {
+                    return true;
+                }
+            }
+        }
+    }
+    // Even without a monitor, basic input capture is available
+    host.default_input_device().is_some()
+}
+
+fn samples_to_wav(samples: &[f32], sample_rate: u32, channels: u16) -> Result<Vec<u8>, String> {
+    let mut buffer = Vec::new();
+    let cursor = Cursor::new(&mut buffer);
+
+    let spec = WavSpec {
+        channels,
+        sample_rate,
+        bits_per_sample: 16,
+        sample_format: hound::SampleFormat::Int,
+    };
+
+    let mut writer =
+        WavWriter::new(cursor, spec).map_err(|e| format!("Failed to create WAV writer: {}", e))?;
+
+    // Convert f32 samples to i16
+    for sample in samples {
+        let clamped = sample.clamp(-1.0, 1.0);
+        let i16_sample = (clamped * 32767.0) as i16;
+        writer
+            .write_sample(i16_sample)
+            .map_err(|e| format!("Failed to write sample: {}", e))?;
+    }
+
+    writer
+        .finalize()
+        .map_err(|e| format!("Failed to finalize WAV: {}", e))?;
+
+    Ok(buffer)
 }
diff --git a/tauri/src-tauri/src/main.rs b/tauri/src-tauri/src/main.rs
index 84a2f01a..157fee9e 100644
--- a/tauri/src-tauri/src/main.rs
+++ b/tauri/src-tauri/src/main.rs
@@ -792,7 +792,9 @@ pub fn run() {
                 });
 
                 // Wait for frontend response or timeout
-                tokio::spawn(async move {
+                // Use tauri::async_runtime::spawn instead of tokio::spawn to avoid
+                // panics when the Tokio runtime is being dropped during app shutdown
+                tauri::async_runtime::spawn(async move {
                     tokio::select! {
                         _ = rx.recv() => {
                             // Frontend responded, close window