I have spent several years repairing all makes of massage chair. I have learnt that even with the same model, electronics can change. When replacing a hand controller I have always checked to see that the frequency of the crystal on the main board matches the frequency of the crystal in the hand controller. Recently I received a chair which failed to respond to the hand controller – checking all parts everything seemed OK. However when I looked the frequency of the hand controller is 11.0592 whilst the one in the chair is 4.0000. With very little or no understanding of how these things really work – this makes no sense to me. My only explanation – could a previous attempted repair have resulted in a mixing up of handsets? I’ve been there before and it’s very time consuming. Is something very wrong or am I worrying about nothing.