I had the problem that Poweramp (PA) always stopped after starting, in a frequency of 12-15 sec. May be 8 times in two minutes.
The problem was caused because I was not aware that after closing my preferred radio channel there always remained a dot in the Google-logo. This happened when I closed radio with a swipe from bottom to top. Later I noticed, when I swipe from wright to left the radio-site closed completely and this dot disappeared.
When there is no dot at the Google-logo there are also no problems with stops in PA.