Peter, when I report a bug, I try to narrow it down to the minimum context that reproduces it. I still think that the problem is related to the .exe. I have clean installs of all version of Winamp after 2.666, with all plugins but in_mp3.dll removed (output plugins aren't necessary, since no song needs to be played). I've reproduced this bug on all hardware configurations I've changed since v2.666 to v2.77 (that's 3 MoBo's, 2 processors, Win95OSR2 vs Win98SE, DirectX vs. no DirectX etc.) and on friends' computers as well.
If the bug doesn't reproduce on your system, there might be two causes:
1) I haven't given precise enough directions as to how to reproduce it.
2) You sistem is of such nature that the bug isn't reproduced.
If you look at my other thread ("7 bugs"), you can see that bug #5, the disappearing cursor w/ PageDown, didn't reproduce on DJEgg's machine, with all his perseverence, but X-Fixer immediately reproduced it.