2000 Accord wiper problems (loud, poor reach)

I have a fairly recently-acquired 2000 Accord. I'm having two problems with the wipers.
First, they frequently don't swing up far enough, leaving about a 4-inch margin of windshield on the left side unwiped. At highway speeds, they tend to go all the way and wipe right on up to the A-column.
Second, they are usually (but not always) LOUD. The go WHOP-WHOP-WHOP, as if they were slamming into some stopper at each end of their travel. But then sometimes (again, at highway speeds), they get reasonably quiet.

Any clues here?

While parked wet the windshield with water and observe wiper motion. The nut that holds the wiper arm may have come loose and allowed the arm to reposition so it is not tracking properly.

Im having the same problem. I think my motor went out because i looked at the "bars" that turn the wipers underneath and the passenger side one isnt turning...I think this IS the problem. I tried the regular troubleshooting for it and thats where Im at now. Can anyone confirm or deny whats going on here?