Hmmm dam it's so weird aye. I haven't got any videos of mine but will try and get one this next week or so.
I've not had my tune done yet but would like to get it sorted, or at least figure out what it is and if it's bad, before the tune.
I'll try and get a video with it running without the cam cover on too.
I have tried 20W-50 and now running 10W-60 Penrite. No change in noise. Mine will appear shortly after start up from stone cold. Isn't so bad at idle but you can just hear it, then it is very noticeable at about 1000-1800rpm, goes away at from 1800-2000rpm and above. When the engine is really hot, it's less noticeable/not at all.
I've got crow cams lifters in - and stock cams.
Yeah my engine builder and a few others have said it could just be those CP pistons. It sounds awful though - almost like an old diesel VW Tourag lol