It looks like having the option to filter by various options has been wanted for a while, and I'm not the only one:
forums.radioreference.com
Being able to set a DMR color code, P25 NAC, PL tone etc to filter what's being received would be very helpful.

DSD+ Feature Request
Can we can a feature to exclude certain color codes on DMR systems? With all of the DMR traffic these days there are multiple users on the same frequency. It would be REALLY nice to mute certain color codes and only hear others. Feature details: 1. Enabled Specify - Sit on specific color...
Being able to set a DMR color code, P25 NAC, PL tone etc to filter what's being received would be very helpful.