Compatability with Sophiscated Backpacks (and possibly other mods that change item stack count)

[704009905]

Sophiscated Backpacks have an upgrade to let each slot have a multiple stack of items, even for unstackables like boombox.
Boomboxes stacks correctly (only empty or that have the same album in it can stack), but when picking up stacked boomboxes if you use right click you will pick one album out, setting all stacked boomboxes empty. Also when you insert one album into stacked boomboxes they will all get one album.

I think this can be fixed easily by not allowing the above two interactions when boombox have a stack count > 1.