Whoa, welcome to the slippery slope smile

Dumb questions to start with:

1. IIRC there are some modes ("Pure Direct" comes to mind) where not only tone controls are disabled but also the DSP processing which generates low-pass subwoofer output and high-pass mains output. Are you fairly sure you were not running one of those ?

2. When you say "... bright sound especially on the high range..." does "high range" refer to "loud" or something else ?

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8