the left and right sliders of each control in the volume applet are 'linked' by a chain below the sliders. When I move the sliders by clicking and dragging, the link gets broken, and only the slider that was clicked moves. If I scroll with the mousewheel it does the right thing. Pulse seems determined to break the link between the two. Either this should be fixed, or the link icon should be removed.
Hmm, cold you please provide me with the output of "amixer -c 0 contents" on your machine? ALSA exports a lot of information about the properties of each volume control slider, this might be set incorrectly on your driver. Among other stuff it flags controls where L and R cannot be manipulated independently.
Created attachment 275421 [details] amixer output sure, attached. something to note also, is that this doesn't always happen. I just tried to duplicate it to be sure it still happens, and it took me a few tries of loading the volume applet and sliding up and down before it broke.
This shouldn't happen anymore since we now extend the hw volume range in software, which means we can always provide what clients ask for, and allow per-channel volumes even if the sound card only has an all-channel volume control. Closing now. If this persists on current rawhide (0.9.12) feel free to reopen.