GROUP COLOR LOST

[Tassy]

Hi 
I do  not know waht I did but pno, as grup, and vox, as stereo track lost their given color in the base

Any idea why it could happen?
I tried to set other colors to try but the base stays out of color.
Never happened in the past 10 years
The normal color (base and name line the same) shown is in the giutars.

Save-reopen... and the colors come back. so all right but strange that such thing could happen
 

Thanks
Tassy