Folks,
My DIR-855 is running under firmware version 1.11. I haven't upgraded to 1.12 as I don't need to use the USB port and I understand that USB port support is the only change.
I'm connected, via a Motorola SBV-5120 cable modem, to Cablevision Systems' Optimum Online Boost service, which is supposed to give me 30 MBPS downstream and about 4MBPS upstream. And, until three days ago, it did.
Then, all of a sudden, my downstream speed is down to 1.5MBPS to 9MBPS and my upstream speed appears to be roughly 1.1MBPS most of the time.
As a result, I just spent the day with Cablevision personnel (four of them), trying to solve the problem. In the process, I discovered that, for the first time, if I connect my main PC directly to the cable modem, bypassing the DIR-855, I get advertised speeds! In the past, when I had speed problems, bypassing my router made no difference.
Something has changed, and it's not the router or any of the router's settings. If anyone can suggest why this might be happening, I'd be very, very grateful!
UPDATE: I tried replacing my DIR-855 with my old DIR-635 and, lo and behold, the problem disappeared.
Regards,
Jeff