In the 5 GHz range can be manually mode only channels 36 40 44 and 48, the channels 52-140 are only available to the router itself in the car / DFS mode can be selected.
Here I quote the Cisco Support answer:
When the Auto (DFS) Dynamic Frequency Selection (DFS) is Applied in Wireless Networks. The router automatically selects a frequency channel with low interference level. You are not allowed to set channel 52-140 as fixed channels, due to country regulation. The router can use thesis channels automatically using DFS.
You can on the IPTV over WiFi connected laptop without any additional settings but look with limitations. After a few hours you get to see no more IPTV image, after the router reboot IPTV works correctly. I have not yet figured out where is the cause of this behavior.
The wireless download speeds in approx 3m distance to routers are between 30 and 70MBit / s in the 2.4GHz range and relatively constant 94MBit / s in the 5 GHz range. The big difference in the 2.4GHz range can be assigned to interference with neighboring WLANs as to test periods up to 15 WLANs could be seen. At greater distances in our apartment (ie a maximum of two walls between the router and laptop and a maximum of 12m Range) to get still on 30-70MBit / s in the 2.4 GHz range, in the 5 GHz range you notice a decrease in transmission speed to approx 15-65MBit / s. The compounds are stable.
Unfortunately guest network is not encrypted!
If router would have no problems with IPTV and guest network encryption, I would give it 5 stars, so I forgive 4 stars.
Edit 15.4.2012:
Router works now no longer in the 5 GHz range. Reboot brings short time 5GHz frequency range back until the next failure. Input and security logs are not working. Cisco Linksys Support can not help proposes Exchange. Because of these defects, I forgive only one star.
Edit 25.4.2012:
Amazon has the old router withdrawn and sent new. Thanks for the quick and smooth handling. Unfortunately, the new router to the problems with 5GHz band from the beginning. In Linksys Support Forum you will find several such cases, all without solving the problem. If you need 5 GHz band, this router should not buy.
Edit 27.5.2012
Linksys Support can save because their answers do not bring solutions. 5GHz stable work since I have the channel manually set to 36. Luckily in the neighborhood just another router in the 5GHz band has been active on channel 100. With the Auto (DFS) setting, there were always failures in the 5 GHz range.
The nonexistent logs to Linksys Support will not comment. Because now dual-band work, I forgive three stars, two stars I have withdrawn for non-working logs and IPTV. When Linksys eliminates these errors would be appropriate a 5 star rating.
Supplement 21.10.2012
Very reliable and faster operation in the last 5 months. Do not reset or reboot was necessary! I have tested even external hard drive to USB, it works, unfortunately, are relatively low write speeds 2-3MByte / s in Wi-Fi and ca 6-7MByte / s in LAN with an NTFS disk. There are no problems with HD content from external USB wireless streaming hard disk. FTP Server also works flawlessly. Firmware Update to version 1.0.04 has problems with logs and IPTV not eliminated.
