Short story:
I've found some cases of two channels being assigned the same channel number. My current example involves a feed with the starting channel number set to 21000.
I suspect this is triggered by changing a channel between having a Gracenote ID and not having a Gracenote ID (either direction). I added a Gracenote ID for Declassified last night. I think I added a Gracenote ID for Modern Marvels a couple of days ago. I think I assigned a Gracenote ID to Bizarre Foods a few days ago, but don't recall for sure.
Longer story:
Last night, I noticed that the Declassified channel was lacking in guide data. At the time, it was assigned a channel number around 21020 (I forget exactly). I spotted a potential Gracenote ID and set it. At the time, I didn't do anything to update the data in CDVR. This morning when I went to check it in the CDVR guide it appeared to be assigned to 21092, but when I checked the M3U, it was assigned 21098.
After reloading the M3U in CDVR, the guide now shows 21098 with the channel name Beach Day but the channel icon for Declassified. The actual guide data appears that it may be a combination of Declassified and Beach Day. If I play it, it plays Declassified.

Unless it would confuse CDVR, I would prefer that the assigned channel number not change when switching a channel between Gracenote and non-Gracenote. I understand it would move from one M3U to the other.





under Windows 11.