P25 Phase 1 Channels in Now Playing Are Flickering When Processing TDULC Messages

[DSheirer]

sdrtrunk Version
master
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Describe the bug
Phase 1 traffic channels are displaying in the Now Playing window and the TO/FROM identifiers are flickering before the call and again after the call. This is likely due to the TDULC message processing where it's clearing the IDs and replacing them from the Group Voice Channel User link control.