Sansamp to Orange Terror 500

[Maggsy]

When I plug my sansamp deluxe into the effects return of my terror bass head the output level is very high (unusable) even with the level control of the Sansamp turned down. Tried it through my Genz Benz shuttle and it's fine. Both amps class D. Any ideas please?

[Skybone]

Is there a master volume on the Terror, or a control for the FX loop?

 

Been doing the same with various Line6 boxes over the years (currently a POD Go), and it's been fine with my Ashdown MAG combo, because there's a master volume. Haven't tried the FlyRig outside the house, but again, it's been fine.