Musescore 4/Website changes instruments back to a Default Sound when uploaded

So, when i create a score in Musescore 4, it defaults any voice part to the choir ahhs, which i and my choir member find annoying to listen to. While i can change the sound in the Mixer and save it, when i upload the score so i can use it from the app or website via my tablets, it autochanges the voice sounds back to the choir ahhs. If i'm using the app, i cant change it. Is there a way to make it save the default sound as something like the grand piano instead, that way when its uploaded i can play it normally, like version 3 used to?