SampleTank 2 & N-track

How do i use more than one instrument


I’ve been playing around with sample tank 2 free.
The problem i have is playing back to different chanels in sampletank.
I create a new midi track and route it to chanel 1 in properties and the output to sampletank. Then put a piano on chanel 1 of the sampletank plugin. I record, and all is good, i have a piano track.
I then create another midi track and route it to chanel 2, and output to sampletank and put a soprano in chanel 2 of sampletank, while I record and i hear the soprano and piano. Then i play back and both are playing piano.

Can anyone tell me why this is so?