Why is oscillator 2 heard when only sequencer 1 is playing on the Subharmonicon?

Each sequencer controls the corresponding pitch of it's oscillator and sub oscillators; however, both oscillators go through the same VCA and VCF. Therefore, even if SEQ 2 is not running, OSC 2 and/or its Sub OSC's will be heard if they are turned up in the mixer because the Filter and VCA are being triggered.