Sonic Cell Bug?

[DEVO-UK]

Hey

I have this all up and running with Logic, but recently, the first channel patch has been changing from a drum kit to a grand piano on some tracks.

The patch name says 'rich grand' but the category says RHY (RHYTHM SET)
When I try to alter the patch ( to load the drums back in), none of the drum patches load up as an option for this channel strip.

Is this a bug?

Best

Alan