What's up with this thing

So I don't know weather to post this here or the bug thread but anyways when I open up the client some guitar music starts playing. See this wouldn't be bad if when you turn off the audio the music also stops. Thing is though it's not stopping. This is annoying and when you only hear this while you play other than the music you are already listening to (Fresh F.M., Youtube, ECT.) If anyone else is having this problem please tell me. I don't want this to just be my computer. Hope this can be fixed but if not I hope it's not my computer.

If you turn off your computer's audio and music continues to play it's your computers problem.
Or it could be an ad, etc.