Well I just got done with the wheel. I took PhantomCow's advice and checked the drive side spokes. Yep, some were loose. So, I tensioned them, doing the ping test to get the tension even with the spokes around them. Once I checked tension on all the spokes on the drive side, I did the same for the non-drive side. Found a couple of completely loose spokes, and some that were just down on the tension so I brought them up. Then I trued the wheel, had only 1/2 and 1/4 turn adjustments to get a bit of a wobble out. When I have a truing stand available I'm going to check it for roundness too. I found that I also have a bent axle so I need a new one. May as well rebuild the hub at that point I guess. I'll get it all figured out. I'll post back once I get a couple of commutes on the wheel and check the tensions again.
Thanks for all the informative help.