Where can I find firmware 3.0.0.4.220 for RT-N66U (B1)

Hi everyone,
I have an ASUS RT-N66U router and I recently updated my firmware from the official 3.0.0.4.220 to the newest offered by ASUS - 3.0.0.4.374.979.

That's when the problems started.
I did reset to factory defaults and re-entered my settings, but now at least once a day my connection slows down considerably. The slowdown lasts for anywhere between 15 mins to about an hour and fixes itself.

I have a 50 Mbps down/10Mbps up connection that usually tests at 57 down 12 up. When a slowdown hits, it can be anywhere from 3Mbps down/ 1 up to 0.8Mbps down/ 0.01 up (according to speedtest.net)


Same thing on WiFi and wired computers. If I plug the computer directly into the modem I get regular speeds.

Modem restart does not fix the issue. Nvram clean does not fix the issue.


So I thought I can revert back to my original firmware (which worked great for over a year) and I went to ASUS's site to just to see all they offer is the last 3 versions (3.0.0.4.276 and up).

Does anyone know if there is a place for me to get the 3.0.0.4.220 firmware from somewhere? I tried searching the web, but could find nothing.

Thanks for any and all help.