So you have been asking for help about this problem but switched through multiple threads, which really doesn’t help. You said that you only get bad sounds out of the QC through the Yamaha HS-8 AND your headphones. So clearly getting another speaker won’t magically solve this.
The problem I would think is that your gain and level settings are totally off.
Try setting everything in the signal chain to zero / default:
On the QC:
set all the inputs and outputs of the QC to zero
set the input impedance of input 1 and 2 to 1M ohm
go to the factory presets and chose a basic one
On your Guitar:
Set the Volume of the pickup(s) to full
turn off the EQ / set everything to the middle position
In your DAW (Reaper):
set the Master Volume to zero (default)
create a recording track, set it to mono and USB Output 3
leave that track at zero (default)
record some riffs
How does it sound now? Can you share an audio clip and tell us what the factory setting was?