The fix for Android based devices mentioned in this thread http://forum.mikrotik.com/viewtopic.php?f=7&t=65270
is still far from optimal.
Android can now connect to the access point but the connection is very flaky with frequent hiccups, timeouts and disconnects.
I have a RB800 with 2 R52n cards running in A/G and N mode. One in 2.4Ghz and one in 5Ghz mode. All SSID's use WPA2 and AES.
Beside the computers I have 4 Android devices currently connected in my network and I don't see any issues and have not seen any before? Currently I run ROS 6 RC4. But as said I have not seen this issue on any of the ROS 5 or 6 releases.
The units are
Asus Transformer Infinity TF700T (Jelly Bean, Latest OTA)
HTC Desire (4.1.2 Evervolv rom, Rooted)
HTC Desire S (Gingerbread? Stock)
Samsung Galaxy S2 (ICS Stock)
All units work with no issues full speed when needed and no disconnects hiccups and so.
Perhaps this is hardware related (Mikrotik or Phone/Tab) I doubt that it is ROS in it's whole.
Has this issue been seen only on the 751U series?