Blenders can be finicky like that after a few months of heavy use so yeah i've fixed a couple over the years by tackling the common culprits step by step. Start by ensuring the jar is locked in properly; sometimes it's not fully engaged & causing vibrations.
Next, examine the blade area. If you can remove it, do so and clean out any built-up residue that might be throwing it off balance. Reassemble firmly. For the shaking, try placing a damp towel under the base to absorb some of the movement.
If it's still noisy,, the issue might be with the bearings or coupler, but that's trickier. I once had to lubricate the moving parts lightly with food-grade oil. a tiny bit. Fixed it right up. And don't forget to pulse instead of going full speed right away – eases the strain.
