Strange behaviour
 

It happens that I have all the DIGI001 outputs routed to my mixer (TASCAM M-2600 MkII). Last week, I don't know why, I've just insterted a Signal generator plugin on an empty 2416 track (PTLe session) at 1kHz/0db. The surprise is that all the output channels between 3-8 on the digi read, on Tascam meter bridge) almost 11db bellow channels 1-2.
It looks as 1-2 are truly +4 but channels 3-8 looks like -10? Strange.... any inputs?