Radios not working when 10 are turned on

We purchased 10 radios to be used at an event. All radios worked fine when tested individually. During event, when all 10 radios were turned on, none of them would transmit or receive properly, even when within 10’ of each other. All radios were on stand by, and only one being used to transmit at a time. Some transmissions could be heard, but only for 1 or 2 seconds until it cut off. When majority of radios were turned off, the others worked fine. Anyone know what the problem is?

Not enough information, ernie. What model and brand name of radio were you using?

I agree that more info would be helpful, however I suspect that these radios are being used in too close of a proximity to one another, or that the tones are not set correctly on each of the radios.