Scanning not as reliable when frequencies not marked as trunked

[CuriousRunner]

I can program an (EP encoded) trunked system containing seven voice frequencies in a couple of different ways. When I set it up as a MotoTRBO Trunk system and monitor all the frequencies including the (fixed) control channel then the scanner will stop quickly on a conversation and works well. When I program just the individual voice frequencies that I am interested in as Conventional channels (and scan nothing else) then the scanner often does not stop on the frequency when it's active or the decode is choppy.

I can definitely understand how this happens with brief transmissions as the scanner will know immediately from the CC info but this system only has a few frequencies and the voice call can go on for a good while sometimes before the scanner stops, if at all. Is there any reason for this? I don't have this issue with non-trunked BP or clear frequencies. (Having said that, I will now try the same with a non-EP system to verify how that works but regardless it is still an issue.)

I have another system where one of the voice channels conflicts with a stronger signal so I just want to monitor one of the two frequencies

I am using a Uniden BCD436HP with V1_99_36.
Maybe this is partly down to Uniden behaviour rather than the custom firmware but I don't know as I haven't used the native Uniden firmware, only openscanner so just querying if this is just a "me" problem? If this is a known Uniden problem then please excuse me and feel free to close this issue. Thank you.

[x27]

I think I'd better ask this question to our community https://t.me/openscannerchat since I don't have trunked networks in my location to test this.

[CuriousRunner]

OK, will do. Thanks.