I have WinAmp 2.91.

Everytime I am stepping through in OllyDbg (or hit a breakpoint), WinAmp becomes unresponsive.
If it is already playing a song, then the song plays fine (it doesn't stutter or anything), but I cannot interact with WinAmp (it does not respond to any keyboard/mouse input).

As soon as I hit F9 in Olly (to get out of single-step mode), WinAmp comes back to normal.

If I have been single-stepping especially a long time, then as soon as I come back to normal, WinAmp throws these "error transacting" msgboxes.

Has anyone else experienced that?

It does not matter what priority class WinAmp is set to. It freezes no matter if it is on normal, high or real-time priority.

For me it helps to uncheck "single-step break" at exceptions debuggion options and continue running only with F9 (not Shift-F9).
What is your exception code? 0x80000004 (single-step break)?

There is no exception. As soon as I enter single-step mode (even if I stop doing anything for a while), WinAmp remains frozen.

Well when you aren't running the program (with F9) the current thread isn't executing. That current thread is probably what runs the GUI that handles mouse clicks, etc. Another thread will be running the sound playback.

I am not debugging WinAmp.

http://ollydbg.win32asmcommunity.net/?action=vthread&topic=29 5&forum=1&page=-1 ("http://ollydbg.win32asmcommunity.net/?action=vthread&topic=295&forum=1&page=-1")