Adding --output-24bit to the TiMidity options in Solfege fixes sound problems for me
I am currently trying out GNU Solfege for ear and rhythm training. Solfege uses TiMidity for playback. On my machine, the sound output always started with an annoying crackling for each exercise. Some googling brought up this solution. While that link has nothing to do with Solfege, following its advice helped in my case, too. To remove the crackling in Solfege, I did the following:
In Solfege, open the File > Preferences Menu Choose External Programs Under Audio File Players - MIDI it should say /usr/bin/timidity (or something similar) add --output-24bit to the options for that entry (my complete options for timidity are --output-24bit -idqq %s) With the Test Button right next to the options you can try if the fix works for you. Whether or not this works for you probably depends on a lot of factors (your soundcard, versions of of timidity and drivers etc. pp.), but if you have the same problems it is probably worth a try.