I have a Sony KDF-55WF655. I think the IR sensor is going bad. My remote occasionally stops working for no reason. I have tried numerous different remotes, but I get the same problem no matter which remote I use. I have changed the batteries as well. The remotes still work the cable box with no problem, but TV functions (volume, mute, power on/off, etc) don't work. The sensor is not obstructed by anything. I've tried unplugging the TV for a while and then plugging it back in. Nothing has fixed the problem. It happens at random times. I'll use the remote to adjust the volume and then the next time I try to adjust the volume it does nothing. Or, I'll mute the TV and then cannot get it to unmute. Sometimes the remote works fine for a few days, and then it will all of a sudden stop working. I don't get it.

I was in my time a tv service engineer and had many a remote do this the IR Sensor at the top off the circuit board has loose soldered joints But you have to take the remote apart to get to it and in many remotes this is not that essay as they are pressed together and may have screws also so you need to look carefully THE parts that are pressed together ease apart with a flat wide say have inch blade at one side half way down the remote you should hear it pop then ease it all the way round and then look to see if the IR is lose if it is re solder Hope this helps Good luck I was in my time a tv service engineer and had many a remote do this the IR Sensor at the top off the circuit board has loose soldered joints But you have to take the remote apart to get to it and in many remotes this is not that essay as they are pressed together and may have screws also so you need to look carefully THE parts that are pressed together ease apart with a flat wide say have inch blade at one side half way down the remote you should hear it pop then ease it all the way round and then look to see if the IR is lose if it is re solder Hope this helps Good luck