Advertisement packets missing

 I am using ellisys sniffer and during tests found that the advertisements are getting missed on some of the channels(1 in 50 times).

For e.g. we can see advertisement only on Ch. 39 and 37 and 38 are missing.

Is there any way by which we can log on nordic device on what packets being sent out?

These tests are done in isolated environment with no other RF interference.