Like George, I suspect a 'buffer dump'.
Like the track hadn't finished playing when you stopped it, and the data left in the audio buffer unloads at startup instead of clearing.

At one point when I was having this issue (I haven't had it it in a long time) I learned through testing that letting the track finish playing and actually end before doing anything would fix it (the buffer gets emptied).
Not sure if this is the same issue OP is having, but thought I'd mention. At the time I seemed to be the only one with the issue, and a couple versions/machines later I no longer experience this so it may be machine dependant.



Make your sound your own!
.. I do not work here, but the benefits are still awesome