These settings typically do not need to be tweaked unless you are experiencing stuttering or other playback issues.
Playback Buffer Size
Lower buffer sizes results in less memory usage and quicker responsiveness when changing tracks, but may skip/stutter more often. Larger buffers typically reduces or eliminates skipping and stuttering, but will result in crossfades taking longer to start after changing tracks.
Playback Priority
Priority of the playback thread. Higher priority gives GMMP higher priority on the GPU but can lag the device.
Decoding Priority
Priority of the audio decoding thread. Higher priority gives GMMP higher priority on the GPU but can lag the device.
DSP Priority
Priority of the dsp/equalizer thread. Higher priority gives GMMP higher priority on the GPU but can lag the device.
Enable OpenSL
An alternative decoder for mp3 and aac/m4a.