Stereo HELP required

Dominic

Using a Strymon Deco as the last pedal to split out to 2 separate combos .......sometimes the stereo is fine but more often one amp becomes 90 % dominant over the other ....ie volume on Amp 1 is at 2 but Amp 2 needs to be on 7 to be balanced .....why ?
 Both amps are approx 20 watts ..........why is this happening ?

fendergibson

1. Are they both the same amp ?
2. Are they valve amps ?

ICBM

If you swap the cables at the pedal, does the same amp stay quiet? If it does, does the same happen if you swap the cables at the amps?

Dominic

Not same amp ;will try swapping cables at the pedal
I should point out that the Deco is running from 1 outlet of a Palmer Triage splitter which makes it a fully isolated loop in its own right with a ground lift , phase reversal switch if needed etc .There are other amps fed from the other 2 outlets so I could actually play 4 amps at once if I wanted .