Asus RT-AC66U iftop probs

[Santi Gaite]

I have decided to install Asuswrt-Merlin on my RT-AC66U, to install and use iftop through Entware. And I do not know if this should work, but in my case something must go wrong, since the traffic that iftop shows in any interface that I try, br0, ppp0 or vlan10 is totally incorrect with respect to what it should be. When I execute it without specifying interface, as if I specify eth0, the router restarts, I tried to do everything from scratch, I even tried to install iftop through Optware, but the result is exactly the same.

I'm adding information, in the RT-AC88U same occurs...

Can anyone clarify something to me?