You should remind your retailer of his statutory obligations here:-
Consumer Rights Act 2015
Goods
The Act requires goods to be:
Of satisfactory quality.
Fit for a particular purpose.
As described.
Previously defective goods had to be rejected within a 'reasonable period' but now consumers have a minimum of 30 days in which they can reject goods that fail to conform to the contract.
So 'good will' does not come into it,
Additionally, if you bought the set wholly or partly (over £100) with a Credit Card, then you have the same (Section 75) right of redress against the credit card company.
If the retailer is a large chain rather than an independent, though, a call to head office, who will likely be much more au fait with the above, may prove more effective,
You might want to say that out of your good will, you will accept a replacement set from another manufacturer, for cash difference.
But you are under no obligation to do so; you can take your refund and go elsewhere if you choose, something that may be conditioned by whether they put up an unreasonable fight or not.
And don't worry that they might say 'see you in court'; the Small Claims procedure in the County Court is simple, swift and inexpensive, can be heard in your jurisdiction not theirs, and is usually much weighted towards any but the most unreasonable of plaintiffs.
(I know, as I have used it - though not to return my Sony Android TV, which is at least usable, even though it is not ideal)
YouView Superuser, but not an employee of YouView, nor retained by them for this purpose. It's purely me speaking
