Unity html5 - performance issues and studio settings


i just changed the audio in my project from inbuilt unity html5 audio to fmod - it builds fine but the performance is pretty bad - lots of pops and audio dropouts as well as some quite impressive stutters at times. turning off the unity audio helps but the problem still makes it unusable. i am not doing anything much just playing a couple of events concurrently and a bit of volume panning using the ahdr and also directly from script.

I wanted to tweak the fmod html5 settings but i can’t seem to get them show up in settings or in studio - desktop seems to be the default platform in studio and there is no option to add html5 as a platform

have i missesd something and does anyone have any general tips for performance on html5 other than what is in the documentation