D-Link DWR-118 A1 - problem with 5GHz - MediaTek MT7610E

I've just bought a D-Link DWR-118 A1 and I have a huge problem with 5GHz. On original firmware, 5GHz work well. With snapshot OpenWrt firmware only 2 meters coverage for 5GHz. 2.4GHz work ok.
The second problem with D-Link DWR-118 A1 with bridge/relayd function. Bridge/relayd works but I can't log in to him from my main router (WAN). To bridge/relayd I used TP_LINK WR740Nv1 also and compared configuration with but I can't find the difference. To TP_LINK WR740Nv1 I can log in from the main router but to D-Link DWR-118 A1 can't.

Does someone have this same problem with DWR-118 A1 with 5GHz? Maybe someone knows a solution? On original firmware 5GHz work very well but on OpenWrt isn't.

Similar problem with driver MT MediaTek MT7610E is Asus RT-AC51U -> support for 5GHz

5Ghz not working for me too...

All Mt7610e devices and in general all Mediathek chipsets are crap under openwrt....

There were already projects going on, but noone really put it into main packaging of OpenWRT.

For my Archer C20i with newest snapshot and 18.06.2 the 5 GHz only works directly in front of the device which means less than 2m and TX power is not adjustable. Also the connection breaks down very easily.