Investigate/remove audiorate element/timing issues

[JamesHarrison]

There's some oddities with timing in the receiver.

Removing the audiorate element appears to do the job.

The decoder appears to spit out audio with some delay in some cases, causing audiorate to insert blank chunks of audio then discard real audio.

There perhaps should be a queue between the decoder and rest of the pipeline but this seems highly variable; some root cause analysis is required first!

[JamesHarrison]

I've removed the element in 040c0f0, having poked around a queue doesn't appear to do the trick and I can't see a major issue with delaying downstream elements in this case.