I'm helping a friend with a site which needs some 'cleverness' (by my lowly standards) playing audio whilst pages are browsed. Checking out a competitor's site

I'm helping a friend with a site which needs some 'cleverness' (by my lowly standards) playing audio whilst pages are browsed. Checking out a competitor's site, I was flabbergasted to see its source was about 8 lines of HTML, one of which linked to a Mb's worth of entirely inscrutable and indecypherable Javascript, leaving me with no means of working out how they did what they dun. Coupled with crap like Instagram with it's locked-in walled garden content you essentially need to sign up for to view (and then, practically, install an app to update (yes, i know there're workarounds!)) we've somewhere over the last few years encouraged a large chunk of the internet to become quite obnoxious and antithetical to everything I understood it was supposed to represent. Bah blast and humbug!