we have a similar issue with MR46, ALL of our MT sensors MT10, 20, 40 went offline and stayed offline, at the exact time firmware was upgraded on the AP's to 31.1.5.1 (latest stable), the AP's report that they are now detecting poor RSSIm -87dBmm cutoff -85dBm, even though they were perfectly fine for weeks before the firmware upgrade!   nb. we are trialling these sensors currently, but obvs won't be using them if they are this unstable! ... View more