Question Sub output really quiet randomly

[Lzcas]

don't know if channel is blown shouldn't be, but I was using rxa cables into my sub output with 1800w twin Edge sub into it and it's so quiet when I put tjem on a or b or anything their really loud, idk why the sub one doesn't do anything now don't know if I've done something in tje amp sbwr is set to 0db, any mode disco, no effect, dolby Pro, does nothing still really quiet no clue why it was working fine yesterday speakers work fine on b I just wanted on sub output so I can control it more.

also when I put any other speakers into it like 20w sub it's really quiet too, tried different cables too


YAMAHA NATRUL SOUND AV AMPLIFIER DSP A592

 

[kerberos_20]

subwoofer outputs are usualy just preamp, that is without amplification (low voltage)
if you can measure voltages on input and output, than you can determine where is fault

 

[Lzcas]

subwoofer outputs are usualy just preamp, that is without amplification (low voltage)
if you can measure voltages on input and output, than you can determine where is fault

it's weird because the otherday it was loud but now it's not I don't know what happened