MP3 (ID3) Tags
BRU 3310
V2 are not supported
An (ID3 V1) MP3 that does not have a Track No is assigned, 32.
An MP3 that does not have a V1 ID3, but only a V2 ID3, is assigned some (seemingly) random (perhaps 9-digit minimum) number.
A file that is not an MP3 (I suppose it is) is assigned a Track No of 0.
Just stating.
Should a file with no Track No be assigned anything at all or simply left blank?
As ID3 V2 is not supported, certainly nothing should be picked up as the Track No (%k).
(In particular when you have a directory with a mishmosh of types of Tags, & you've selected them all in BRU.
Similarly I'd think there would be no reason to assign 0 to a not MP3.)