Frigidaire bad compressor ?

I have a 2 year old frigidaire refrigerator that quit cooling. I had a local repair guy come out. he said the compressor is running and sounds good but it is just not cooling, said i would need a new compressor. he based this by saying the voltage was good going to it, just wandering if there could be a bad relay or switch he didnt seem real sure of himself thanks

Feel the compressor, if vibrating and warm, your start device is ok, but the system has a refrigerant leak/ bad compressor.