ls. 

Cactus Music
 
Your audio interface pre amps gain control/ pad will determine all incoming levels

This would be the first thing I would check...the pad switch
 
My Focusrite Scarlett 18i20 has a small button for the pad, easy to overlook.

I did not find OPs answer to the key question (asked By Anderton):
How low is it? What are the (Master Bus output) meter peak readings when the track slider is set to 0 ?
That figure would be a most important hint.
If the project contains commercial (mastered?) loops, as the OP says, the level of own recording may sound low compared to them, even though it's on the recommended level (around -12dB - -6 dB).
 
"I always have to process those tracks with gain or normalize, but then I get distortion."
As normalizing alone should not be able to produce distortion if the level is kept below zero, I assume the distortion
comes only with gain lifting?
 
 

Kalle Rantaaho
I did not find OPs answer to the key question (asked By Anderton):
How low is it? What are the (Master Bus output) meter peak readings when the track slider is set to 0 ?
That figure would be a most important hint.
If the project contains commercial (mastered?) loops, as the OP says, the level of own recording may sound low compared to them, even though it's on the recommended level (around -12dB - -6 dB).
 

This^

Following some of the advice given, I went into Windows and did two things. I unchecked the Windows microphone. I also unchecked something that was like "reduce media volume by 80% when making a phone call." I didn't have a mic with me at the time to check each one individually. When I got home and plugged in a microphone, I had normal input levels.
 
Thanks very much to each of you who responded! I really appreciate it!!! I wouldn't have thought of either of those two things.
 
Take care.