There was some small debris caught in the fins at the bottom of the sump. I took out the cover panel for the sump pump fan, cleaned the area removing all debris, and reassembled.
I'm running a Finish Dishwasher Cleaner pack through a full Power Wash cycle now, to see if that eliminates the sounds. The initial start up did seem to be noticably quieter, but I'll keep an eye or rather an ear on it, to see how it does through the full cycle.
As I'm writing this, I'm listening to the various sounds. It still seems a little loud when the pump is emptying liquid into the drain (I can hear the water going into the sink drain pipes). Still 90 minutes to go in the cycle, so I'll keep listening.
Dishwasher is running through it's second full Power Wash cycle now. It sounds a bit better but not 100% yet. The sump looks totally clean after I manually cleaned it and then ran a Dishwasher Cleaner through it's full cycle. I did notice that the drain filter has some mineral deposits built up, even after the dishwasher cleaner finished. Would that contribute to the noise? If so, I could soak it in some CLR or similar product to get rid of that.
Any other ideas of things I could check?