Wireless Snooper

Hello dear MikroTik community,

Pre: We want to implement indoor location-service using Mikrotik hardware. We are going to scan customers MAC-addresses and CPE signal levels to DB. The problem is that CPE`s are conncted to 3-rt party vendors AP. So we have to use snooper to scan the wireless spectrum.

The Problem:
When you do Wireless Sniffer sometimes there is a packet (highlighted) which shows wrong signal level from CPE. If this packet is the last in a group - Wireless Snooper will show this (wrong) signal for a while. In practice wrong value may be valid for a couple minutes (jittering from time to time) and then repeat randomly.

Question #1:
Is it possible to filter in wireless snooper (flat-snooper) CTS/ACK packets to show more correct signal-level values?

Question #2:
Maybe there is a more simple way to get valid snoop results? - Signal level from any custom CPE connected to any AP.
Screenshot from 2019-02-26 13-15-54.png