When I play files using in_gsf (v0.11, dunno if that's the latest), I get about 0.5 second of nice clear audio and then some filter is applied to the audio even though I have both filters off.
VBA-M with blargg's GB APU is used in viogsf. (How many times have I posted this?) Highly Advanced uses VBA's old core. Portability and channel muting are other nice features of viogsf. Finally, Highly Advanced's code is a mess while viogsf's (courtesy of Mysterious Plugin Guy) is nice and tidy.
There probably have been some minor updates to VBA-M's PCM rendering as well.