Help using 4CM with a Marshall JVM410

[Paincakes]

I found this thread that I am linking here to bookmark for myself to try adjusting levels

Instrument vs. Line Level for the QC's FX loops

Hi guys, I’m loving my QC, but I have a new bass amp (Mesa Subway TT-800) and cabinet (Mesa Subway UltraLite 1x15) on the way and I’m working out some ways of making the two play nice together using the four cable method. One note that I was given by agedhorse over on TalkBass is that the FX loop on the QC will have to be set to instrument level for best results when using the four cable method with this amp. I don’t see options in the ins and outs section of the unit or in the FX loop blocks …