iPlayer double capture problem

[castalla]

I've suddenly got two capture streams on iPlayer video - one contains the word 'streaming' along with many other hexadecimal (?) characters - this completes successfully. At the same time there's a second capture stream with only hex characters - this just continues capturing until I manually delete it.

Occasionally, there's only the unending stream - so the capture fails.

Using Firefox 3.0.9 and FoxyProxy 2.9.

Anybody else seen this problem?