My TV is a pre smart TV, about ten years old. The remote stopped working. Got two new ones, don't ask! And they worked fine but the fault is now back intermittently. It's completely random, no time connection, it may work all evening then not then, five minutes later it works. Both new controls work when it does and don't when it doesn't. Any ideas on that one? I know it's quite old by today's standards but it's a good enough one for us and, as we're retired we don't want to have to buy a new one. Help!