I am a new owner of the ASUS RT-AC66U and have it running the official 22.214.171.124.270 firmware. I also have the ASUS PCE-AC66 PCI-E card. I've just come to the very odd discovery that transfer speeds are nearly double when I login to my Synology NAS and download files with the browser (Firefox), versus doing a basic file copy in Win7 over SMB share. This is as reported by the RT-AC66U built-in traffic monitor tool and copying/downloading the exact same file. With Firefox, files are downloading at an average of around 35 to 40 MB/s which I understand is about what should be expected. With a basic Win7 file copy over SMB, I am seeing speeds of 12 to 15 MB/s. This phenomena is completely reproducible. To illustrate, here is a screenshot from the traffic monitor tool of the same file being copied twice from my NAS: the first time as a Firefox download and the second time as a Win7 file copy over SMB: Any thoughts would be appreciated.