I was annoyed at not having any contact from Apple so I waded through their hefty customer support system and requested support without a charge considering it a hardware problem.
This only resulted in an option of me giving them a call when it "was convenient to me", in the email they sent through it only showed U.S. phone numbers. So after searching their support pages I found a UK 0844 number and rang it.
I explained everything and was transferred to someone who tried to deal with it who then said they would ring me back.
Have now had two calls from Apple support, very nice of them to reply to me at last.
They have, as expected, blamed my Toshiba TV and said they were being helpful to me in trying to resolve the problem with that TV, even though it was not their problem as far as they were concerned.
Told me it was the Toshiba's Cinema Mode causing the problem. Toshiba disable the Cinema Mode when in use with HDMI input so this is not true, as there is no control of this when using HDMI signals.
We rented Tangled at the weekend, very funny, but this showed the stutter more so than any previous videos, so I have told them this and that I will not be renting any further videos on this device and also will not be purchasing Apps for my iphone or itunes again until it is resolved.
They have now passed on my details to a "Senior Engineer" and I am awaiting their response again.
We live in hope but I am not optimistic in this case and am beginning to wonder if they cannot fix it how difficult will it be to get my money back as I have had the device since December now...