diff --git a/codec/h265parser/parser.go b/codec/h265parser/parser.go
index 0521a09c..5117d64f 100644
--- a/codec/h265parser/parser.go
+++ b/codec/h265parser/parser.go
@@ -537,8 +537,31 @@ func (self *AVCDecoderConfRecord) Unmarshal(b []byte) (n int, err error) {
 	self.ProfileCompatibility = b[2]
 	self.AVCLevelIndication = b[3]
 	self.LengthSizeMinusOne = b[4] & 0x03
-	spscount := int(b[5] & 0x1f)
-	n += 6
+
+	n = 23
+
+	n += 2
+	vpscount := int(b[n] & 0x1f)
+	n++
+	for i := 0; i < vpscount; i++ {
+		if len(b) < n+2 {
+			err = ErrDecconfInvalid
+			return
+		}
+		vpslen := int(pio.U16BE(b[n:]))
+		n += 2
+
+		if len(b) < n+vpslen {
+			err = ErrDecconfInvalid
+			return
+		}
+		self.VPS = append(self.VPS, b[n:n+vpslen])
+		n += vpslen
+	}
+
+	n += 2
+	spscount := int(b[n] & 0x1f)
+	n++
 	for i := 0; i < spscount; i++ {
 		if len(b) < n+2 {
 			err = ErrDecconfInvalid
@@ -554,15 +577,14 @@ func (self *AVCDecoderConfRecord) Unmarshal(b []byte) (n int, err error) {
 		self.SPS = append(self.SPS, b[n:n+spslen])
 		n += spslen
 	}
-
 	if len(b) < n+1 {
 		err = ErrDecconfInvalid
 		return
 	}
 
-	ppscount := int(b[n])
+	n += 2
+	ppscount := int(b[n] & 0x1f)
 	n++
-
 	for i := 0; i < ppscount; i++ {
 		if len(b) < n+2 {
 			err = ErrDecconfInvalid
@@ -570,7 +592,6 @@ func (self *AVCDecoderConfRecord) Unmarshal(b []byte) (n int, err error) {
 		}
 		ppslen := int(pio.U16BE(b[n:]))
 		n += 2
-
 		if len(b) < n+ppslen {
 			err = ErrDecconfInvalid
 			return
@@ -579,24 +600,6 @@ func (self *AVCDecoderConfRecord) Unmarshal(b []byte) (n int, err error) {
 		n += ppslen
 	}
 
-	vpscount := int(b[n])
-	n++
-
-	for i := 0; i < vpscount; i++ {
-		if len(b) < n+2 {
-			err = ErrDecconfInvalid
-			return
-		}
-		vpslen := int(pio.U16BE(b[n:]))
-		n += 2
-
-		if len(b) < n+vpslen {
-			err = ErrDecconfInvalid
-			return
-		}
-		self.VPS = append(self.VPS, b[n:n+vpslen])
-		n += vpslen
-	}
 	return
 }