Vibrating outdoor unit, Goodman MSC 15, 8 years old

Hey all,

I have a Goodman MSC 15 Split type wall mounted AC unit with an outdoor unit.

Everything seems to be functioning properly as far as cooling goes, but the outdoor unit will vibrate pretty aggressively for a few seconds when it starts ramping up intermittently. The vibration causes visible movement to the unit's case and the grill on the back. It's standing on a four-legged metal stand with vibration pads between the unit and the stand, and a vibration mat under the stand itself. I'm not sure if this is normal or indicative of a problem. It's not particularly bothersome to me other than the concern that the movement is bad for the unit.

I'm curious if anyone with experience is familiar with this type of issue?

Thanks!