You won't want to hear this, but if you changed your Tx crystal your radio needs to be sent to a service facility and retuned. Your range will probably be diminished if you don't. Given the trouble you just had, a checkup is a good idea anyway.

If you're flying with 10 year old stuff, are you using the original batteries? If so, that's probably the cause of your problem. Most of us toss our batteries after 3-4 years of use because they deteriorate.