The Android app still sends notifications even though I have them all turned off in the app. Doing a search it looks like this has been an issue for people for over 3 years. I disable notifications in apps because I don't want to be bothered in the middle of the night by a random app that thinks I need to now, at like 4am, check out new songs from someone.
Fix your crap, Soundcloud. It's ridiculous that such a simple thing that has a reasonable chance of causing disruption to people's lives wouldn't be solved for years on end.
I've disabled notifications externally, but this means I won't get the notification when I'm actually playing music that lets me control it from the slide down bar, so that's not really ideal. I'll likely just uninstall it all together, because if I can't play music conveniently or I have to get woken up and bothered by your app I'll choose to just not use your app and site altogether.