iPlayer issue/ADSL24

I am having issues streaming HD iplayer in the evenings, its fine during the day.
I am on ADSLmax, 4.5k profile with ADSL24 (Murphex).
BTspeedtester reports a nominal drop in throughput during peak times but HD on iplayer really struggles and the iplayer tester seems to report a disproportionate performance drop off.
I have had a support ticket back and forth with my ISP who say my PC is at fault as it may not have enough graphics capability etc (strange how its fine during the day then).
Iplayer requires about 3.5 meg to stream HD happily so for some reason during peak it really struggles despite the BT speedtester reporting in throughput in excess of this during peak.

Other users reported similar issues a while back and an issue was found at the ISP end of things, but this was raised when their customer service was better

Any ideas?

Have you tried the iPlayer Speedtest during times when you see the problem?

http://www.bbc.co.uk/iplayer/diagnostics

This will identify any issues between your machine and BBC's iPlayer content servers at the time you normally see a problem and may help.

Matt

yes, I have ran the bt tester and the iplayer off peak showing successful tests, then ran the tests at peak which showed a marginal drop off on the bt test and poor results from the iplayer test. My ISP requested screenshots of both the bt test and iplayer test etc which I gave them showing several successful tests and the slowdowns. They then passed it onto their "network engineers" and the response that came from them was-

"The issue the customer is experiencing is not network-related and does not fall within our support remit. Streaming HD video is more reliant on the user's hardware setup than on their connection speed.
The first image in the list you sent me is from the iPlayer's own connection tester, which actually factors the capacity of the computer itself as well as the user's DSL speed.
HD videos are highly compressed, relying on a decent CPU clock speed, decent RAM and reasonably decent video card to effectively translate the data. The result they received indicates that their computer's current setup is not capable of HD streaming."

That doesn't sound very helpful.

Have you thought of perhaps moving to Sky or a TT Business Wholesale reseller?

Incidentally, your exchange in your sig is incorrect. You have transposed the last two letters.

lol, sig changed- been like that for years and not noticed

Sky have recently enabled LLU but I read positives and negatives, undecided as yet. Plus I like the idea of spporting a small fry rather than Murdoch!