You don't have a contract with Humax once your warranty expires. You have statutory consumer rights, which make the retailer the liable party. UK consumer rights are actually better than the EU rights, as it's seven years before all protection expires.
You might like to check the Citizens Advice Bureau's website as they have a lot of good information on consumer rights. Be warned, it's a lot of hassle, and may get you nowhere as you would have to prove it was defective when purchased, or not fit for purpose, or whatever grounds you claim under.
I'm not a lawyer, just telling you my understanding.