I have a similar issue to all the adblock issue threads that are being posted, but for my YouTube instead of displaying a white screen of some sort with a "Skip Ad" button, it says that an error occurs with playing the ad itself. Here is the image. It shows on the timeline the duration of the ad but it skips past it after 5 or so seconds. Sometimes it shows two different playback ID's, but every time it skips past them and then plays the video. I doubt there are any fixes for it at the moment, but I hope this might help with fixing the issue.