Hello, JohnDH!
I came across your post and was with the same issue (same laptop by the way). I found a configuration in a similar issue from march-2020 here in the community that solved it for me:
[No sound on selected videos or other multimedia from the web - #7 by tompro]
“Can you try going to your sound settings:
windows settings --> sound --> advanced sound options --> app volume and device preferences , and adjust the settings for Brave.”
On my lenovo, Brave was locked to always playing in the laptop. Changing it to “standard” made it change from speakers to laptop as I plugged the speakers in or out. Hope it helps out!