Default [Q] Issues with music player and bluetooth

Hello all, I listen to music via bluetooth and my car shows track information using AVRCP. Since updating to 4.3, this works well only with the stock music player. If I try to use Poweramp/Shuttle, the track information in the display doesn't change after the first song, and gets stuck there, even though other songs are playing. When using Pandora, track information isn't displayed at all. Any ideas on how to fix this? Thanks in advance.