Here's an update for those with an interest in this on-going issue.

We shipped back a clients player which, we understand, suffers regularly from the sticking buttons problem. After extensive button-pressing in circumstances similar (maybe even identical) to those described by the client we have been unable to reproduce the problem.

We're now trying to determine what could be different about the client's environment/actions to cause the problem to manifest itself. It seems likely that if we can reproduce the problem reliably, we'll be able to fix it, or at least find a work-around. It's perplexing that we haven't been able to reproduce it even once, whereas the client can consistently experience it within the space of a few minutes.

We'll keep trying!

Rob