C5180 All in One Network Problem

I recently bought a C5180 printer/scanner/copier. I'm happy with the print
and scan performance, and would really like to make this unit work.

The printer attaches either via USB or wired Ethernet. I have it attached to
my D-Link DI-524 router in one of the Ethernet ports. I use my MacBook
laptop almost exclusively wireless. I have no problems with my computer
operating in this mode. However, printing is unreliable in this
configuration. Most draft quality printing is fine, but occasionally fails.
Photo quality printing almost always fails. It will print part of a photo
and stall. Eventually, the printer will spit out the photo and go back to
it's idle mode. However, the print monitor on the computer thinks that
printing is still going on. I'm guessing that the two have had a break in
communication. I can bring up the printer status displays in a browser and
it appears to be happy as a clam.

If the laptop is connected via an Ethernet cable, then everything works
fine. I've never had a print failure. Scanning works either way.

I've installed the latest drivers from HP, changed cables, restarted
everything multiple times, etc. The problem is repeatable. If the laptop is
wireless, printing is unreliable. The only thing I haven't done is swapped
out the wireless router since I don't happen to have another one lying
around.

Has anyone else encountered this kind of problem? Any suggestions?

Thanks