Hi, I have a DEH P9400BH head unit and I really like the Advanced Sound Retriever function for mp3's. A caveat is that it can only be used for USB connected devices it seems. When I stream from bluetooth the mp3's aren't as nice sounding as from the flash drive.

Does anyone know if there is a similar type of app I can install on my Android device that does this? I assume some sort of DSP function would work, but from what I can tell, most of those are pay apps, is there one that is free?