Regarding channel trim levels - viewing and changing them on the fly is documented on page 37 of the owners manual (far right column "To adjust channel levels during playback:"). You use the "test" button on the remote, press enter (to leave test tones off) then use right and left to move between channels and up and down to adjust the level.
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Outlaw Audio Model 976 / 7700 / Ultra-X13
B&W CM9, CM Center, DS3 (side), DM303 (back)
Blue Jeans Cables (XLRs, Canare 4S11 Bi-wire, HDMI)
Tivo Bolt, Xbox Series X, Panasonic ub820, AppleTV 4k, LG C765P
Roon, Allo Digione Signature, Sonore MicroRendu, Uptone Audio LPS-1, Peachtree Audio Nova 150
GIK Acoustics Soffit Bass Traps, 244 Panels, Monster Bass Traps, QRD7 / Polyfusor Diffusers