Hi, It's been a while, but I'm coming back to XmPlay... almost. From foobar2000. Winamp is long-gone in my book.
Point is, great work on the sid plugin, loving filter distortion, and 2SID support. However, just one little bug with combined waveforms in 6581 mode. The bug is most noticeable with /MUSICIANS/A/AMJ/Pashaus.sid. While the waveforms sound like the 6581, the 8580 response is evident. Comparing with sidplay2/w, or rev. 26 of the plugin. IE, anything resid-based, not residFP-based.
Speaking of residFP, which version of the lib are you using? There's a 0.2 beta out, perhaps that might fix the waveform problems?