8192cu routerboard bpi r1

I installed 19.07.4 on a banana pi r1 board. Despite the problems with low speed on ethernet wan interface, which have been solved with reconfiguration of the wan and lan ports, I am suffering with wifi's low download throughput. For some unknown reason the download on the AP is maxed to 2Mbit/s. The upload is fine with top of 40Mbit/s. This is first time I have met the assymetric throughput in the 8192cu adapter. I know that the 8192cu driver is a long time member of the kernel driver's family, but this the first time I have met this. I also tried to use the 8xxxu driver, but the 8192cu adapter is not picked by the driver at the boot time. I also tried to adjust beacon interval with minor effect on the speed.

Am I missing any hidden setting in the driver that enables tweaking of the download speed?

Don't expect this to improve.

After a bit tweaking with options txantenna 1 and rxantenna 2 I have managed 71Mbit/s with iperf. The speedof.me portal give back speeds about 35 Mbit/s which is a slight improvement. However, the upload rate was not problematic at all. The result is not stable for a production environment yet.

After putting the basic rates and supported rates in the wireless options, the luci wifi interface disappeared from the menu. Does that mean, these options are not supported in the luci environment?

Just tried the 22.03 rc4 image hoping that the situation with wireless gets better. I have got 8-9Mbits with iperf, but after reconfiguring the wan ports, the speed on cable wan port is just 17Mbits in comparison to the full speed in the 19.07.4 image. Any reason for this degraded performance in the 22.03 rc4 image?