There is an electronic repair shop in San Juan Cosala that works miracles on TV's, stereos etc.
After you enter town from Ajijic, continue to the first traffic light. Just past the light is a long white wall with a huge microwave tower behind it. At the far (west) end of the white wall is a shop with a blue awning. The shop is called "Teleservicios Calvario".
Don't let the picture discourage you..... Great service and very reasonable