We just use one wireless microphone but we also have a wireless sax, wireless bass, wireless X-Air mixer and Wireless IEMs, and haven't had any drop outs or anything. We found that we had a problem with the new Nux Sax wireless, the range wasn't great (certainly compared to the mic), so I now attach an XLR and hang the sax RX up near the front of the stage and the range is hugely better (ie, over double), so maybe that was inteference of them being plugged straight in the desk a few cms from each other - all the other wireless things are connected elsewhere.