I have a TS-520S and D-104 mic that I bought several years ago. I rewired the plug on the D-104 and it works like a champ. The only problem is that it only works in VOX mode. If I lock the key down and switch VOX on I can transmit. However, turning VOX off and keying the mic gets me nothing. I have scoured the web for a solution and have not found anything. Could anyone give me a clue as to what is going on and how to fix it?