Has anyone had 4K blu-ray discs that have gone bad ? I have a few now that were perfect when bought, but now the picture breaks up and freezes about 40mins in. The discs are perfectly clean and there’s not a mark on them ( i look after my discs ). It’s not the machines as i have three of them and they are all saying the same thing, 2 Panasonics and Oppo 205.
Could be Disc Rot
Microscopic corrosion due to moisture in the air and not properly vacuumed when manufactured. 
Never had this problem with normal blu-ray and DVD.
All I can think off . 
I’ve seen it on CDs
Thank you, i appreciate your reply.
I’ve seen it on CDs too but it usually starts near the edges and is visible to the naked eye eventually. Usually impurities in the substrate which was more likely on some CDs which were effectively “cut out” meaning the substrate went right to edge of the disc and is exposed where it is cut out by a machine. Better discs are sealed at the edges. And all the BR discs I’ve seen (and I have absolutely hundreds) are perfectly round and sealed at the edges.
Are you able to confirm the problem on multiple players? 4K discs do require finer firmware controlled focusing than standard discs.
The machines are the Oppo 205, Panasonic DP-UB820EBK and DP-UB9000 all award winners. The Panasonics still update whereas the Oppo hasn’t for quite a while now, but the problems are the same.
And all the affected discs have the problem at 40mins? Weird.
There is something called Blu-Ray decay which is the chemical breakdown of the layers in UV light. When not used, discs should be boxed and away from sunlight.
I really can’t think of anything else.
Indeed - this suggests it’s not any form of disc rot, since that would affect different discs at different rates so the fault wouldn’t manifest so consistently.
If it really is affecting multiple discs identically and the problem is identical on different players… I’m all out of suggestions. Maybe take the discs to a suitable dealer and ask if you can try them on their kit?
Mark
@Super
I have about 150 4K discs and been playing them on a Panasonic 9000 for about 5-6 years now and have never had any problems.
Is there anything common about the discs that wont play properly, like where and when they were manufactured/same movie company, how they have been stored/where they were bought from etc that may indicate why they are failing?
1 Like
I’ve had a few that do this when there is a tiny trace of fingerprint on there. A spot of glass cleaner and a microfiber cloth and all good again.
I did all that even though there was no marks on them and still made no difference.
Probably something no one thinks of doing for low value items but, have you contacted customer support of the manufacturer? You can usually go to the Warner Bros. Universal etc. website and at least get a support ticket. You need to look at the fine print on the back though. Sometimes the manufacturer is licensed to a different company or studio.
I rip all mine to a giant NAS so they don’t really get played more than once so their exposure to anything to go wrong is limited. But I’d be pretty annoyed if after a couple viewings they became defective.
You might get a free replacement out of warranty. You never know.
Yes, I’ve had this issue, even on new discs. As I understand it, there is a residual film that can be on the disc that causes this issue, but it’s pretty random it seems. I’ve found that a clean with my record cleaner fluid (which is basically isopropyl alcohol and water) with a microfibre cloth usually fixes it.
1 Like
Had disc rot with a load of HD DVDs
1 Like
Only ever had it on 1 cd it had a little brown spot I tried to polish out but it still played but I replaced it instead of giving my laser a hard time. 
1 Like
would like to do this, how to go about it? (ripping to a NAS)
You need a decent BR drive like a Pioneer and possibly a third party firmware hack to allow it to read 4K, a Windows PC, and a bit of software called “Make MKV”. That’s your ripping taken care if.
For playback, if you want mobile access and sharing, you really need Plex Server on the NAS and a Plex app on your video streamer (Amazon Fire Stick, Roku, shield etc.) But for ultimate quality playback and simplicity, you need no software on the NAS at all. Just use Kodi app on your video streamer. It will read direct from the NAS file share without the need of any UPnP server-client.
If you are only home streaming with Kodi, you can probably even avoid using Make MKV and just rip discs to ISO files, but you’ll end up using a lot more storage. ISO support lets Kodi mount the file and treat it like a disc with full interactive menus and extras. But ripping with Make MKV forces you to be more selective about which video streams (usually just the main feature) and which audio and subtitle tracks to include or omit.
You can expect discs in 1080p with DTS-MA or Dolby True HD to average out at about 30GiB and 4K discs about 80GiB. And older DVDs around 5GiB. So size the NAS appropriately.
1 Like