As you may be aware, the Poweramp developer has been working hard on an updated material design user interface for Poweramp v3 which required a full ground-up rebuild of the code and is taking some time to get to a beta-test stage. See the forum thread for more details and to discuss, but it is currently hoped that the next Beta Test release will be ready for April 2018.
Few months ago i had volume issues in poweraamp. Volume goes down suddenly and when i unlock my phone volume goes up. I have to disable and enable DVC again and again to maintain normal Poweramp output.