| JVC | AV28SD4EK MXIV | No sound and all programs show the same channel | Check the data lines on pins 14 and 13 of the connector CNO13 on the sound subboard. If they are low, disconnect the lines one by one from all the chips until the correct level is restored (about 4 V p-p). Also check IC001 5V regulator for DJs, as this could be the culprit. In this case all 3 chips on the sound board had leaky data line inputs: | 14-09-04 |