WE3526 low speed

Hello
I have ZBT-WE3526 5Ghz speed is very low.
Openwrt version 19.07.05-07
Provider give me 500Mbits and if i use wire, i have all.
When i try to connect use WIFI, its very slow
2,4 is more faster as 5Ggz.

6.0 Mbit/s, 20 MHz
585.0 Mbit/s, 80 MHz, VHT-MCS 7, VHT-NSS 2

Speed test 4 meters to router, one brick wall
Connecting to host 192.168.1.197, port 5201
[ 4] local 192.168.1.100 port 63661 connected to 192.168.1.197 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 7.61 MBytes 63.8 Mbits/sec
[ 4] 1.00-2.00 sec 7.95 MBytes 66.5 Mbits/sec
[ 4] 2.00-3.00 sec 7.17 MBytes 60.3 Mbits/sec
[ 4] 3.00-4.00 sec 7.52 MBytes 63.0 Mbits/sec
[ 4] 4.00-5.00 sec 7.74 MBytes 65.0 Mbits/sec
[ 4] 5.00-6.00 sec 8.67 MBytes 72.6 Mbits/sec
[ 4] 6.00-7.00 sec 8.76 MBytes 73.5 Mbits/sec
[ 4] 7.00-8.00 sec 8.82 MBytes 74.0 Mbits/sec
[ 4] 8.00-9.00 sec 7.47 MBytes 62.7 Mbits/sec
[ 4] 9.00-10.00 sec 8.69 MBytes 72.9 Mbits/sec


[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 80.4 MBytes 67.4 Mbits/sec sender
[ 4] 0.00-10.00 sec 80.3 MBytes 67.3 Mbits/sec receiver

iperf Done.

0,5 m frome router
Connecting to host 192.168.1.197, port 5201
[ 4] local 192.168.1.100 port 63668 connected to 192.168.1.197 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 12.8 MBytes 107 Mbits/sec
[ 4] 1.00-2.00 sec 13.1 MBytes 110 Mbits/sec
[ 4] 2.00-3.00 sec 15.2 MBytes 127 Mbits/sec
[ 4] 3.00-4.00 sec 15.8 MBytes 133 Mbits/sec
[ 4] 4.00-5.00 sec 13.4 MBytes 112 Mbits/sec
[ 4] 5.00-6.00 sec 14.8 MBytes 124 Mbits/sec
[ 4] 6.00-7.00 sec 13.1 MBytes 110 Mbits/sec
[ 4] 7.00-8.00 sec 15.1 MBytes 127 Mbits/sec
[ 4] 8.00-9.00 sec 13.3 MBytes 111 Mbits/sec
[ 4] 9.00-10.00 sec 13.6 MBytes 114 Mbits/sec


[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 140 MBytes 118 Mbits/sec sender
[ 4] 0.00-10.00 sec 140 MBytes 118 Mbits/sec receiver

What i try

  1. change Maximum transmit power
  2. change chanel, auto and choose one
  3. and try different security settings. Now use wpa2
    Factory firmware Openwrt 18 and speed test show 300+

what could be wrong?

Have you tried setting channel width to 80MHz? Are you sure all four antennas are in tact? On my own WE3526 running 19.07.7 I'm getting 300-380mbps ac Wi-Fi throughput using iperf3 (from ac enabled Chromebook to another laptop connected to the router via gigabit ethernet).