WZR-1750DHP change 2.4 GHz channel

[CapnBry]

First of all can I say that "Second part of word in most Buffalo Products" is a really difficult captcha for someone who only owns 1 buffalo product at a time and doesn't know the full name of the product which is "WZR-1750DHP AirStation™ Extreme AC 1750 Gigabit Dual Band Wireless Router EXTREME PERFORMANCE". Took me a few tries to get through. Anyway!

In wireless settings for wl1 (2.4GHz) on my WZR-1750DHP (build 23709b). When I set the channel to anything but Auto, when I press the "Save" or "Apply" buttons, the combo box immediately resets to Auto before doing the apply. The only way I could change the channel was to telnet in and nvram set wl1_channel=11

Even now if I just hit Apply on that page it switches back to Auto and I have to telnet in to change it back to 11.

My settings (including wl0 as well in case there is some interaction):
wl0 mode: AP
wl0 Network mode: AC-only
wl0 ssid: capnbry
wl0 wireless channel: Auto
wl0 channel width: 80Mhz
wl0 extension channel: upper upper
wl0 ssid broadcast: enable
wl0 explicit beamforming: enable
wl0 implicit beamforming: enable
wl0 network: bridged

wl1 mode: AP
wl1 Network mode: NG-mixed
wl1 ssid: capnbry24
wl1 wireless channel: Auto
wl1 channel width: Auto
wl1 ssid broadcast: enable
wl1 network: bridged