Arrrghhh! Duplicate 'Ghost' Audio Track Driving Me Nuts!

I keep experiencing the most annoying intermittent bug with audio...

Out of the blue and for no reason I can identify or replicate, voice audio from another clip in the timeline duplicates itself over another clip (so I hear 2 voices at once).

However, the duplicated audio track is no where to be seen. Even if I disable the visible video and audio track it still plays! If I blade the clip and then stretch it out again, it reappears - as though it's attached to it permenantly in an alernative dimension.

The only way to resolve it is to delete the entire clip - which is a nightmare if the clip is long and heavily edited.

It's happened to me at least half a dozen times now over various builds (inlcuding the latest release) and on 3 different machines.

Any suggestions?