I'm in the same boat... DIR-825 & DAP-1522 running at 140 Mbps; 300 Mbps desired. No solution yet. I'm somewhat convinced that it's an issue with the DAP-1522 since I have another N device (MacBook Pro) that's connecting at 300 Mbps.
Exact same problem here, and they're both going back to the store tomorrow morning if I can not find a fix somewhere on this forum tonight.
I was getting 18-21 Mbps TCP streams from my 11G network with frame burst enabled ... I just went out and dropped $260 on 11N gear to increase that to a whopping ... *drumroll* -
------------------------------------------------------------
[148] local 172.30.0.25 port 53297 connected with 172.30.0.130 port 5001
[ ID] Interval Transfer Bandwidth
[148] 0.0-10.0 sec 28.5 MBytes 23.9 Mbits/sec
Not a CHANCE I am keeping this stuff if that does not improve.
And it is not interference or stuff in between point A and point B ... I was only getting a 140 Mbps link when the devices were 1.5 feet apart!
And yes, 300 is the "theoretical max" and all that, but 140? Seriously? How can you defend that? My 11G connections bounced between 54 Mbps and 48 Mbps, as I said, giving me 18-21 Mbps real-world TCP throughput. What I am getting with this new gear is an absolute joke.
I'm using the 5 GHz interface, restricted to N, WEP2/AES, and Auto 20/40 (although this setting doesn't seem to stick in the UI).
I had a DAP-2553 earlier today, but didn't have a chance to test it with either other device... too bad.
Same here ... you have to set it to A+N to make it stick ... as soon as you flip it to N only it goes back to 20 MHz ... I have no idea what that is all about but I am not impressed as I had planned to run a pure N environment so there wouldn't be any slowdowns from backwards compatability.
D-Link was already on my "do not buy" list before I saw these products and decided to give them another chance based on the capabilities their Wifi certifications claimed they could do. If I can't get these talking faster than 140 Mbps when they're TWO FEET APART it will be going back on my "do not buy" list, in bold, with stars around it, and I will have to start warning friends away from D-Link products as well.
I'm going to try playing with the alignment as mentioned earlier and failing that I'll be back to dig through the forums some more.