@ritea
Hi,
I have Archer C6 and the same issue here.
Have you the guest network for 2.4GHZ on ?
Try to run your A6 without that network and look if the problem goes away...
5GHz guest network can be on, no matter.
For me it seems to run now, but still testing.
The firmware is buggy, i have this 2,4GHZ dying, since i turned on the 2.4GHZ Guest Network.
And all firmware for Archer C6 have this little nice bug.
Best Regards