LibreTube - uses Piped as video source by default. Subscriptions and playlists can be created, all without actually interacting with YouTube.
Clipious - uses Invidious as the video source. Also allows for subscribing and accounts. Lesser known client
NewPipe - Gets the source directly from YT. Allows for subscribing and creating playlists
Additionally, there’s also ReVanced that lets you patch the regular YT app to include useful features.
If LibreTube is not working for you (the reader, not OP), enable HLS here:
3 dots > Settings > Audio and video > Use HLS
See this.
That’s what I remember doing when I set it up, is this due to differences in CDNs across continents?