1. Can I delete my feed?

    Not manually. Feeds are automatically deleted if not used for more than 90 days.

  2. I am trying to turn the link below into a podcast form (to listen to on my phone) and it doesn't seem to be working? https://www.youtube.com/watch?v=XXxxxXXxXxX

    Podsync can't build a feed from just one video. You have to provide a link either to a channel, user, or playlist.

  3. Audio podcast is double the length of the video, and the second half is silent

    This is known issue. Unfortunately as of now I don't have any fix for this.

  4. I am trying to download some files, but it is giving the following error "Download failed, error code 403 forbidden". Is there a solution?

    That happens because you're in a different region than Podsync. More details on this here. I've been working on multi-region support, fix is coming soon.

  5. Does feeds auto-update as new videos show up on YouTube? Or do they just represent a snapshot of whenever you generated them?

    Feeds are cached for 10 minutes to reduce server loads.

  6. Is it possible to get a podcast of all videos in "watch later" on YouTube?

    No, that would require "login with your YouTube account" on Podsync. Instead you might want to create custom playlist and add there videos you want to watch.