Check your SNR in Engineers Menu and see what you have-it should be above 30dB or thereabouts. If it's below that it will be known as stuck in tune and you will have to go through the guide to replace various capacitors in the box. I have one here which has a low dB of around 19-20 and Chookey pointed me to the 2 Capacitors near the card reader-heat them up and you will see SNR rise and stay-I'm waiting for the caps to come and will change them-worth trying to see if yours is the same. Look at TwoBeercans TUT on Stuck in Tune and it will show you what to do.