First of all RF converter DVD to try both audio cables after you unplug the machine, trouble still. RF output RF converter plug from the TV unplug-and-trade, outdoor antenna plugs, test drive everything works, judging failure on the RF converter. Open the converter's lid, measuring audio converter

Oscillation tube voltage of Q1, base 2.5V, launching 1.8V, base voltage is greater than the emitter voltage, the Q1 has stopped vibrating, came into operation (oscillation State, the base voltage should be less than the emitter voltage). Upon checking found that the C4 (56pF) welding, welding test machine after all normal, troubleshooting. When measuring voltages of Q1, base 2, 4V, launching 2.6V, base voltage is less than the emitter voltage, Q1 is oscillation.