Bolymic 4 x100 Channel UHF Professional Wireless Cordless Beige Skin Color Headset Headworn Microphone mic System for Stage Presentation Theater Speech Drama Stage Play (FCC Compliance)

After doing one show with these mics and only having minimal issues, they have completely tanked during our most recent show. The mic packs that you see in the picture are NOT the ones that I received, and the packs that I got do not allow you to change the group or channel. There is no center button on the face of the transmitters. The packs are locked on one set group and channel and can't be changed.Even with brand new batteries we experience a lot of dropping in and out. I have switched out for new lav mics and I get the same result. I can see the connection drop in and out on the receiver throughout the show even though the actor is standing on the front of the stage standing still. This was not happening 6 months ago. Perhaps they are only durable enough to last through a show and a half.__________________________________Old Review_____________________________________________I bought these for my high school drama department. Costs are always a huge obstacle for us. I decided to take a chance and get these to add to our old set of Shure BLX4 and Countryman mics. They worked great for the entire production. Set up was straight forward. Didn't need to adjust frequencies. The range is great. I personally don't like the double over-ear headsets. They are harder to work with hair and costumes than the simple over one ear mics. Sound quality was good, but there wasn't any singing in this show, so I can't say too much about the microphones' abilities in that regard.At this point I would totally buy them again to further expand my mic inventory. I've used plenty of super expensive microphones for the past 10 years working with our local community and semi-professional theaters, and everywhere I've performed there were always mic issues. I think these are a great value for the price.