I've personally found, I had an old samsung galaxy phone, that leaving the app going all of the time in the background would cause things like that to happen. I would normally fire the app up to use it and then shut it down when down.
However I just got a new phone yesterday so I will have to reevaluate how it behaves on my new phone.
N1XBM
Apparare Scientor
Paratus Communicare
Allstar Node # 27086, 41540, 41812, 42086, 42658, 42657
www.radioguysrepeaternetwork.com