I have never heard he used trackers at all, he used his own programming skills back in the old days.
I would love to hear something from him again, but I doubt he’s going to be making it with that special c64 sound feeling, but i’ve read he made a soundbank for quadrasid. Right now i think he use his spare time on a orchestra project!?
Interview with the maestro:
maybe the guys here know:
Forget hexadecimal. Back in those days, one would create a tune using pure machine code. Of course, all Rob Hubbard would need, being a god, is sheer force of will. In the later days there were C64 trackers available but these weren’t used in any games I believe.
His myspace page - not so certain he runs it or not -
Here is a video concerning Rob Hubbard and Jeroen Tel’s music - performed by the c64 Orchestra.