crystal issues
 

I am having some radio enterference(spelling) issues. I am tryn to run losi tx
the ones that come with a micro and mini with Traxxas RX. Is this my problem or do I have something wrong? If I run a car on channel 1 and a car on channel 2 they cause problems with each other. We ran our Losi Micros 4 at a time with no isues, but now using the same crystals I am havin issues with my 1/10th cars. Also do they make more than 6 channels in AM 27mhz? I also have some 75mhz AM stuff but I need to buy crystals for them. Any help would be great. Thanks