env/ohbm: a way to "permapause" the radio on the main page

[yarikoptic]

even if it adds no performance hit (but I have heard about "no free lunch") to the what seems now longer time to load the main page of the event (https://ohbm.sparkle.space/in/home), it is quite annoying to have it start playing every time I go back to main page, even if I paused it when I was previously on the main page. That might also interfere during conference with ongoing audio/video calls (may be outside of the venue platform, or just in a separate tab). So it would be highly desirable to be able to
"pause" it permanently somehow.

And I think it was not like that before, i.e. it wasn't always re-starting when I was getting to the main page, so may be some recentish change in behavior.

[yarikoptic]

@margulies mentioned that it might be easy to just turn it off "by default" in admin interface. Would be suboptimal but still a better "default" IMHO.