I get noises on the guitar tracks (signal chain while tracking or too much compression ?)
I can imagine the vibe you are aiming to but I'm sorry to say you have a lot of timing issues that are in the way for me..
It might be that I'm a drummer but, even if there isn't a drum set in the final product, having a rithmic instrument or a click to record helps to lock things together..
Don't forget anything heard with a certain level can be in the way of the rithmic integrety like the bass fret noises..
I'm sure it could be a wonderfull song if I could get passed the timming and the noises.
Thanks for sharing !

It's hard for me to tell whether this is a good song or not because I'm not able to get past hearing all the glitches - all the way through the entire song - it sounds like it may be a part of the bass track, (fret noises? If it is that, then they're the hottest fret sounds I've ever heard.)

But I can't narrow that down to be sure... it almost sounds like distortion, but it's happening randomly, and sometimes in between downbeats/attacks.

Maybe a playback buffer problem? It's got some of the signature click and pops that are indicative of that... yet it's only happening on the one side...

I think what may be more important to ask here, is how did you not hear this problem before you okay'd this mix and posted? Or, did you hear the problem and thought it to be okay?

Also, FWIW, the vocals are very pitchy (both lead vox and harmony vox), and timing-wise, the instruments aren't locked-in with each other.

My advice to you would be to take this one back to the drawing board, as you have both engineering problems and performance issues.

Heard a lot of glitches, and you had a lot of room at the start that didn't compliment the recording.

How do I go about fixing those playback buffer pops? Get a new computer?

I'm not entirely sure you have buffer pops.. but usually you could increase the buffer value in your DAW and in the interface's drivers.
The first thing I would address is tighting up the timing and try to record the bass without so much noises.
Use a lot less compression is a starter point !