Please upload a debug log and post just the token URL that is generated after the log is uploaded by running the following command from the Pi-hole host terminal:
Unfortunately, Pi-hole has no control over the queries it receives. It can only answer, and in this case the answer is the answer you have specified. I would visit the forums for the soundbar and see if there is any insight there.
*** [ DIAGNOSING ]: Pi-hole log
-rw-r--r-- 1 pihole pihole 11M Jan 28 22:27 /var/log/pihole.log
-----head of pihole.log------
Jan 28 00:00:21 dnsmasq[17838]: query[PTR] 1.0.168.192.in-addr.arpa from 192.168.0.70
Jan 28 00:00:21 dnsmasq[17838]: /etc/pihole/custom.list 192.168.0.1 is skyqhub.lan
Jan 28 00:00:24 dnsmasq[17838]: query[PTR] 1.0.168.192.in-addr.arpa from 192.168.0.70
Jan 28 00:00:24 dnsmasq[17838]: /etc/pihole/custom.list 192.168.0.1 is skyqhub.lan
And you will continue to see the same warnings as long as your soundbar continues to repeatedly request the same domain. This is outside the control of Pi-hole, which can only respond to queries it receives. That is what Pi-hole is correctly doing.