Redmi 3 (Ido) slow wifi connection

Bug description: Wifi speed is slow
Affected version: MK90.0-ido-200910-RELEASE
Steps to replicate: This is not occasional bug, it is always whole time from boot

Hello, thanks for amazing work. I have installed MK90 on my Redmi3 Ido device, everything is working fine except wifi. Wifi is slow, tested download/upload and did advanced tests with networking benchmark tool iperf3 on local network. I get speed between 1-2 Mbps transfer on 65Mbps link connection.

Image 1: Connected to AP with strong signal:
Image 2: Tested download/upload on 30/2 ISP connection
Image 3: Tested download speed with iper3 on local network
Image 4: Tested upload speed with iperf3 on local network

If you need any more tests, or logs, please instruct me, and I’ll post results.