I have found a serious problem with the SPC playback, and this only affects one known game so far. The game is Shin Togenkyo, and the problem is already there when dumped.
The problem starts in Audio Overload 2.0b7 and later on the Mac. The problems range from the audio glitching out after either a second or less than a second, to the audio simply cutting off after either a second or less than a second. Audio Overload 2.0b6 and earlier play the tune fine.SPC file of the test tune from Shin TogenkyoComplete WAV audio output file of the test tune from Shin Togenkyo from Audio Overload 2.0b65-second WAV audio output file of the test tune from Shin Togenkyo from Audio Overload 2.0
(WARNING: Crank down the volume! This is the one that glitches out!)
Yes, that's a wedding tune. ^_^ You can directly access this tune in the actual game by waiting at the title screen.
The tune shown here plays fine on Audio Overload 2.0b6, but glitches out on Audio Overload 2.0.
This isn't good news for me, as usually this plays pretty much all of the other SPC files fine.
(I am ignoring Dark Law's SPC set from SNESMusic.org, as this has the same problem, but this is related to fixing a first-note sticking problem. I can easily utilize a patch from the Script700 page that makes the tune compatible with Audio Overload 2.0.)