Y-Axis noise/grinding

Greetings!

Long time lurker and learner. New to cnc and recently bought a used x-carve (i think its the oldest version with the dewalt 611). Works great! Learned a lot and am finally making lots of fun stuff.

Well, right as I start milling up lumber to make xmas gifts for folks, the machine starts making a grinding/rubbing noise as it travels the y-axis. It happens through the length of travel and is isolated to one side. It seems to be carving fine except for the noise and vibration - which i assume will lead to a failure at some point

I tried to upload a video but even the 15 seconds was too large. Imagine something like a bad bearing in a car wheel or maybe plastic gears skipping…

There are some threads on this topic but they dont seem to offer any clear steps to test for causes or resolutions…

If any of you pros out there have advice, I am all ears and if youre willing to spend a few min on it I will get a properly sized video uploaded.

Thanks in advance!