New Setup Volume Issue

I'm going to be that guy whose first post is a plea for help. I hope this is the correct area to post this.  I've looked here and other places but cannot find anything definitive about what the issue could be.

I recently bought what I guess you could say is a budget friendly setup.  The components are as follows:

Speakers: Polk Monitor 60 series
Amp: Onkyo TX-8220
Phono Preamp: GoGroove Pro Preamp
Turntable: Fluance RT82

When playing through the turntable, the issue is how much I have to crank the volume on the amp and the gain on the preamp to get anything considered even remotely loud but at the expense of sounding absolutely dreadful.  There is little to no output at all when volume is below 50%.  I tried using the preamp built into the Onkyo unit as well with slightly better results.  However, using the Bluetooth input and optical audio input (from a PS4), produced much louder sound as well as sounding much better.

I realize that this is far from a high end system but I expected better results than this. My question is this, could this be solved by getting a more powerful preamp or is it the amp itself that is the limiting factor?  I am open to any suggestions.  Thanks for the help.