Specific channel selected will only get 20mhz bandwidth.

[SoulGI]

Device Information:
OS: MIUI 13.0.5 Android 12
Device: Redmi K30 5G
Software Version: 2.19.1

Problem:
When I tried to start hotspot in VPNHotspot with specific channel selected, seems i can only get 20mhz bandwidth. I don't know why. Is it a bug, or a feature?

Example:

1. When I set 36 as the channel for Wi-Fi hotspot, then start hotspot in this software, I can only get 20mhz bandwidth.

2. But when I restored the setting to default, then start hotspot in this software, I can get 80mhz bandwidth. (80mhz is my device max supported bandwidth because it was released in 2020)

[Mygod]

There is a bandwidth option to tweak.

[SoulGI]

I don't understand where is the bandwidth option. The "AP band" option seems only have two selectbox to let me choose two channel?

I can only find these options(without "Network name" for personal reason). Maybe the OS of my phone didn't support that?

[SoulGI]

Ok, seems I found the answer. I checked the source code, and found this option require API 33. But my device only get Android 12 (API 31) officially. So that is the problem.

But when I try another device which has Android 14 (API 34) support officially, seems I can not control the bandwidth as well. I saw the option is "Maximum channel bandwidth", but seems the option is no use at all. For Example, if I set it to 40Mhz or 20Mhz with channel 36, I will always get 80Mhz. Maybe Xiaomi's HyperOS is not compatible with this option, I think.