Mike1969 ... In order to address your issue with treble, we must first address another underlying issue which can cause multiple sound problems... "DVC (Direct Volume Control)" and "Bluetooth DVC" can cause multiple volume, Bass level and distortion issues. These two features should be disabled. [[[ To do this, go in to settings>audio>advanced tweaks> uncheck direct volume control for both Wired Headset) and BT headset (Bluetooth) this will increase your volume to where it should be. Took me a bit to figure out but it fixed my Poweramp low volume issue" ]]] ( credit to Shinigami Mai of Android Central Forum for the portion above in Brackets [ ] ) Now that we have that out of the way, here is how to solve the treble problem: Whether you have DVC enabled or not the following issue will occur in version 2.0.10 or later. When using The Equalizer in Poweramp, if you try to increase the level of bands 2K, 4K, 8K, or 16k it will cause the treble knob to stop working. It seems that this is some sort of a glitch. The current Poweramp version that is available as of this comment is version V3 build 703 Alpha. In this latest version the issue is still not fixed. A workaround is to turn the "tone" button off and strictly use the equalizer to change the bass and treble.