I've tested this same (Pinnacle USB) tuner and Kaffeine on Void Linux and it works fine.
When I do a channel search in kaffeine it seems to find all the channels, but when I play them they look scrambled almost like old cable TV channels you didn't pay for. (I'm only using a TV antenna; no cable.)
mplayer and vlc will not work at all and I am completely confused about how to use them properly with a TV tuner.
I think something artix (or arch-) specific broke kaffeine.
However, gst-play-1.0 (and totem, which I guess is just a frontend GUI to gst?) plays fine. Problem is, it lacks all the convenient features of Kaffeine.
GST_DVB_CHANNELS_CONF=~/channels.conf totem dvb://WEDQ
I used w_scan2 to generate my channels.conf. (Attached as channels.txt)
Well, the only workaround I have found is to use the command line player mpv, which has at least a few nice features: subtitles (press j), toggle fullscreen/windowed (f).
In order to make mpv work, you need to have a channels.conf in ~/.config/mpv. Generate it using the instructions on the arch DVB-T (https://wiki.archlinux.org/title/DVB-T#MPlayer_/_mpv) wiki:
w_scan -ft -c [country_code] -M >channels.conf
and then launch mpv with the channel name, e.g.:
mpv dvb://WEDQ
The wiki contains more info and a handy lstv.sh script to list channels, but this totally sucks compared to kaffeine. I guess there is something wrong with its backend, libvlc. I can't get VLC to show TV either, but it might be something wrong with the channels file/playlist format.
Details about my hardware: Pinnacle 801e SE USB tuner and Thinkpad Yoga 460 (Intel Skylake GT2 HD520).