I noticed that the audio control keys (back, play/pause, skip) and mute/unmute keys use different F keys on this keyboard (F9-F12) than they are on my keychron,

I noticed that the audio control keys (back, play/pause, skip) and mute/unmute keys use different F keys on this keyboard (F9-F12) than they are on my keychron, external mac keyboards, and internal mac keyboard (F7-F10). This keyboard also lacks volume up/down controls. I wonder why? I understand the lack of backlight control (I don't think this keyboard has a backlight?) and leaving out mission control and expose since those keys have changed every few years in macOS. But volume control is a strange one to omit. Maybe that's what the "rotary encoder" does? This webpage does not make the purpose of the rotary clear, unfortunately. Moreover, it's strange to use different function keys for these functions for... no apparent reason. Especially if you're not going to put any primary function on F3-F8, why not stay consistent for muscle memory reasons? I'm also curious if this keyboard HAS to use bluetooth, or if it's capable of wired control via the usb-c cable like my keychron. I hate bluetooth lag, so that's a dealbreaker for me. This webpage should clarify. This keyboard looks pretty nice, otherwise. As someone who doesn't care to ever use page up/page down/home/end keys, I'll definitely check it out if something ever happens to my K2.