Well, alas, your bug report is invalid
I can guarantee you that it cannot be reproduced with a clean install of Winamp 5.04 with NO 3rd-party plugins.
From your list, it could be any of the following to blame:
Thomson mp3pro decoder (very buggy p.o.s.)
Netamp (never heard of/used it before)
Or one of the DSP plugins (whichever one is currently active).
btw, what is "ofs"?
/moved from Bug Reports to Tech Support