RED BAND in FCPX Timeline

Ever find a solution to this? I'm experiencing it with some footage I shot, and I can't understand what the issue is here. I just upgraded to 10.0.9 today- still there. No matter how I re-import or move the files, I still get the red band over the timeline. My Event Library clips don't show any footage past my first 2 clips. Every time I re-link, it shows me it needs to re-link more than a dozen of the video files (though the clips do NOT show that red with missing file sign, so I'm lost). Right after I re-link, I can again re-link, and again and again. Nothing ever seems to re-link, but nothing appears un-linked to begin with. The clips just don't populate, and dragging it all down to the timeline produced the red band over it every time.

I have sent Apple quite extensive data on this problem and to be honest, I haven't noticed it occurring since 10.0.6. Also, I have only noticed it relative to retiming clips and the use of optical flow. I do recall another user commented that it was observed with media relinking also, but I haven't experienced that.
Apple informed me at one point that it seems to be an internal error that is not supposed to be visible to the user.

My initial reports to Apple were when the application was at 10.0.3 revision and under OS 10.7.3.

If you are interested, some of the research data is attached. Also note that some of the issues documented have also been found to be bugs within early releases of FCPX and may not be specifically tied to the RED BAND issue.

Thanks for the details Dan. I'm going to contact Apple with my details to try to nip this in the bud. If they miraculously have found a solution, I'll pass it along.

The file format was RAW DV (.DV). Just solved it- I re-imported with Optimize Media checked off and everything's there and the band is gone. Still not understanding why it saw 20 minutes of the 4.5 hrs, and nothing else. I would think if the format wasn't supported, nothing would show up. RAW DV isn't a supported format?? Seems that an old DV codec would be supported, but that seems to have been the problem. It isn't listed in the FCPX supported codec list.

I just experienced this issue just thought I would share my details. I'm trying to test out a process to shoot high resolution iPhone video. I'm shooting with the full sensor at 4032 x 3024 since it's 4:3 I'm planning to shoot anamorphic and then "desqueeze" to 5363 x 3024 for 16:9. This format does not record sound with the app I'm using which is Mavis. I created optimized media to try out the Lock & Load plugin from Core Melt with it and it created the red band and blacked out all the video. I deleted the optimized video tried it again and it worked, so it seems it was inconsistent.

I've run into the red band too. www.fcp.co/forum/4-final-cut-pro-x-fcpx/...m-shut-down-playback Never did figure out the cause and haven't had it show up again lately. Puzzling.

It's 2022, and I am dealing with that bizarre red band on my timeline. I rendered this region and the red line doesn't go away. Every time my play head crosses that point it slows down and drops frames a lot. I tried every tip I found here, but I am still getting the same results. Sometimes, the red line goes away but the dropping frames issue remains there. It seems like if FCP doesn't play the render files, it continues to process the effects as if I wasn't rendered them. I think the solution could be to export every one of these red lines regions and reimport them to the timeline. I am working in an "old" iMac Late 2015 - Big Sur. Thanks!

I haven't seen anyone mention this for a long time, but having had the same problem, I did eventually find the solution. Credit goes to Doug Metz on Creative Cow:
He says, "I was able to reliably reproduce the problem in any other project by simply adding preroll to the TC setting. It gets confused rolling through zero.

Edit – tested on several projects with different frame rates. When preroll is added, you may not see the red bars initially, but simply disabling / re-enabling various clips will reveal the red bars."
creativecow.net/forums/thread/unusual-fc...eline-render/page/3/

Also on the Creative Cow page, Hamdani Milas says, "It’s the last thing I would have thought of, I’ve been offsetting the project timecode to allow for colour bars and black preroll for years."

Being a very old VT engineer and editor, for my own amusement I was also in the habit of starting a Project's timecode at 23:59:00 for bars and clock, so that the first frame of programme is at 00:00:00:00. Some Projects would behave for a time, but would eventually show the problem. Now I use 10:00:00:00 for the first frame and 09:59:00:00 for bars and clock.

What happens when the red line is there varies from stuttering to no audio and all sorts of messy chaos.

Incidentally, you can just change the starting timecode for the errant Project and it all comes good – you don't have to make a new Project or anything.

One can only surmise that the database within the Library wasn't written for this scenario.

I don't have FCP to hand right now, but I seem to remember still getting the problem on 10.6.1 with old unmodified Projects that I opened.

At least we now know what causes the RLOD!

TC crossing over midnight. This is a completely forbidden situation. This is why broadcast editors typically start the program at 01:00:00:00 or 10:00:00:00. This allows time for tone/bars, sales, and countdown.

I appreciate that it is now, in the old days not so much...

The main thing is to check the timecode on a Project to see if starts 'before' 00:00:00:00.

Thank you very much, Rinaldo!

I solved it by changing the cache folder's location to another drive (SSD). I delete all my renders and let FCP render all the effects again. Now it's working fine, and the red line has vanished. Could it be related to the bad performance of my old external drive? If a drive is too slow for the job, maybe FCP uses this red line to talk with us, besides the drop frame warning. Isn't it cool?