wired works/wireless doen't

I have something new to me here. I recently installed a 70V PA in a conference center. after it was completed, we tested the system with their wireless mics & everything was fine. A few days later they called and said that they weren't working. What I determined was, I can plug a wired mic into their inputs and everything is works, plug a wireless in and nothing...?
I have double checked receivers, cables, etc. The one ting I have left is to take one of my own wireless systems there and try it and see if it works. If so, I guess both of their systems went out at once...??? i don't know. Am I missing something w/ a 70V system and wireless mic systems? I'm stumped. Thanks in advance.
 
Re: wired works/wireless doen't

Thanks for the ideas everyone, I've had a lot going on and haven't been able to make it back. As it turns out, even though the correct mics were matched w/ the correct receivers. Some bone head at the facility changed the frequency select (inside the mics) on both systems...why? the world may never know. Maybe I took the job away from one of his buddies, who knows. Anyway, all is good. Again, thanks for the replies.
 
Re: wired works/wireless doen't

Thanks for the ideas everyone, I've had a lot going on and haven't been able to make it back. As it turns out, even though the correct mics were matched w/ the correct receivers. Some bone head at the facility changed the frequency select (inside the mics) on both systems...why? the world may never know. Maybe I took the job away from one of his buddies, who knows. Anyway, all is good. Again, thanks for the replies.

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