Drum machine modulation destinations

Hi folks,

Been contemplating the OP-1 again, but haven’t taken the plunge. I can’t quite remember which parameters in the drum sampler engine that were available as modulation destinations for the LFOs. I use a lot of randomness in beat making, but I remember the OP being limited in this. Has anyone got a list of the available destinations? I usually assign a random LFO to sample starting point, for example.