Probem on Pi MusicBox 0.7.0RC4

I have installed a Pi MusicBox 0.7.0RC4 (Release Candidate 4). It didn’t start to play a youtube song.

I did a sudo apt-get update and apt-get dist-upgrade. But now both youtube and spotify didn’t work properly. Just as the past, youtube didn’t start to play. Spotify started to play only after I click and move the time bar on that particular song.