Seq4: Switch Instruments in drum track

Hi,

I am using a Midibox Seq4 with latest firmware in Combination with iPad BLM.

It is no problem to switch nstruments in BLM. But how can I switch Instruments on the Seq4 itself? I am pressing <Trigger> and or F3 and or Performance layer 3 but I cannot switch between for example BD and SD. Any ideas?

Greetz

Chris