wAP LTE Kit - Modem signal level ( RSRP, RSSI, SINR, RSRQ ) via SNMP

Device: wAP LTE Kit
RouterOS: 6.41rc52

Like You see on the screenshot after device boot SINR, RSRQ RSRP values are correct reported via snmp from device, except RSSI ( showing wrong 0dBm always after reboot ).

But after a couple o days ( various time ) something happen on MT device ( blue markers on screenshot ) and all previously working field (SINR, RSRQ, RSRP) start reporting wrong values via snmp: 0dB(m) ( didn’t check on winbox - my bad ). But what is more interesting RSSI start reporting good values via snmp.

Of course after device reboot ( red marker on screenshot ) all back to the previous state and repeat.
wAPLTE.jpg
Here is a another issue about snmp: http://forum.mikrotik.com/t/snmp-interface-stat-shows-wrong-value-for-all-virtuals-interfaces/113539/1