A:Answer A quick follow up.
I contacted Samsung Chat: Use the Samsung remote!
I called Samsung, the lady who helped me had me reset the soundbar (Press and hold both the + & - buttons on the device for 5 seconds). On first glance, this seems to have worked, the AppleTV remote is controlling the sound, but it always did if I unplugged the soundbar. I will give this a go, and maybe the reset process helps someone else.
Overall, I have no other issues with the soundbar, it does what I expect it to do.