I shared my mods of Apollo app XDA forum with the following changes:
-Compiled with Linaro 4.7 Toolchain with Fidelity Edition flags optimization (-O3/Strict-aliasing/etc.)
-Raised the handler thread priority level to high priority audio level. Normally it was set to background level but if you want to turn this to music phone, that level of priority won’t make sure you’ll get good music without being interrupted.
-Increase performance on caching system. It may consume little more space but should improving disk caching performance significantly. I decreased load factor from 0.75 to 0.5 so it shouldn’t consume much more space like 0.25 (Or maybe I should)
-Reduced buffer size and output latency in disk caching. This should some what improve performance for low latency audio playback.