BBC radio 3 on iTunes 320k stream is only 64K

When I am using my satellite for other purposes e.g. recording a TV program, I listen to BBC Radio 3 stream on iTunes. I was very pleased when the "High" stream appeared, which is stated to be 320k. I cannot get BBC R3's own stand alone player to play in HD, as I am currently not in the UK. The standard BBC stream is in iPlayer very poor quality out of the UK and often sounds like a 1960's transistor radio playing through 10 metres of drainpipe.

However in iTunes all is not as it seems. On the Radio 3 "High" stream, my downstream networking telltale is only showing 8 kiloBytes/second = 64 kilobits/sec, not the 40+ kiloBytes I would have expected. I have checked with other streams, e.g. Radioio Classical 128K and that shows just over 16 kB/sec, as it should. Similarly the Amsterdam Royal Concertgebouw 256k stream shows a downstream rate of around 33 kilobytes/sec, which is again what might be expected. Does this marry up with other folks experience. If this is the case, then Apple should not be showing that the BBC Radio 3 stream is 320K, when it patently is not.

Wilson