Your comments

No it just halts in its initial position.

Yeah, it should, but it doesn't :)

So is this a bug? Or is Facebook even lowering the system media volume manually which would not use Audio Focus at all?

You could use a user's Dropbox or Google Drive to sync everything, which is zero cost for you :)

I also have the problem, but only a few times. It happened much more often in earlier versions of XiiaLive.

When I get a Facebook Messenger notification sound, the music from XiiaLive fades out and sometimes it doesn't fade back in again.

I also don't know why Facebook Messenger interrupts XiiaLive at all - I enabled "Ignore audio focus" in XiiaLive?!

+1 for adding this to the lock screen.

If it's not possible to add new buttons, I'd also be fine to use the jump back/forward buttons for tagging since I never use them on the lock screen. Could be configurable :)

Any news here? Cloud sync sounds awesome :)

I'm tired of typing all the song titles manually on my PC.

I have the same issue with Galaxy Nexus running Android 4.3.

When I seek once, it jumps to the beginning of my buffer.

Sometimes it's worse: No matter where I seek, it says "Buffering 0%" and that's it. No sound.

It gets even worse when I seek while losing connection.

A common use case of mine:

If I know that I'll enter an area where I lose the internet connection or it is so bad that streaming is impossible then I seek back so that the music doesn't stop while in that area. I expect it to continue smoothly once the internet connection is reliable again - just skipping the part of the stream where it lost connection. That barely works :(