Sounds more like a loose wire in the rx lead- check the pins are fully seated into the plug, and that they inturn seat fully into the rx it self. While you're at it, check all the wiring over for damage- could be the crytal, but unless you have a spare to check the orginal against, you may have trouble finding the route of the problem (besides bad driving skills
). You lhs should be able to help with crystals if needs be.