Josh,
I'm in contact with D-Link and they'd like a details run down of your configuration before you loaded WRT if possible please.
If you could give us all HW Mfr and Models being used. ISP, Router and Airplay devices.
How it was all connected.
Any and all networking, router and device configurations, use of any router features like Port Forwarding, wireless modes used on main host router, anything that you have that would be helpful so that D-Link can reproduce this issue.
Please list the steps your using to set this all up.
D-Link is reviewing this.
They would like a saved config file to review from the router as well if possible.
We hope that D-Link will change the behavior of the grayed out WMM check box too. They are looking into it.
Any and all information is appreciated.
Thank you.