Well i am using stock room kitkat 4.4.4, i installed the mod for raise up speakers volumen. I am using Poweramp to play music.
I use arome installer, and use both 6db and 12db mod and them i try play music again and i can confirm the volumen dosen't raise up like before. I rollback with an android backup i do before and the sound was normal again.
Sent from my Nexus 5