Gents, I have had this freezing several times on my mitras units... however after trying to find out why, I came to the conclusion its related to the used wireless communication channel. If you have other domestic equipment (microwave for example) in the surrounding area that operates on the same frequency the Mitras unit(s) can freeze-up. It took my several channel adjustments (15 [2425mzH]) before it stopped happening... try it maybe it stables out your issue too?