Doepfer

Hi there. 

I recently buy a a-155 and i need to use like a arpeggiator. 
The problem is: All key give the same tone

My doepfer config is:

1x 110
1x 131
1x 140
1x 118
1x 180
1x 155
1x 145

Im using a roland sh-09 to control doepfer by cv/gate.

Another question: the a-155 has a switch with 1v, 2v and 4v. What is that?

thanks