OH NO! Buffer overflow problem RE-OCCURS with NXCAM

[Adam Welz]

Hi All

after Sony replaced my HXR-NX5U and my FMU128 unit, I had a buffer overflow and total crash again today with the new ones.

I was using Sandisk Class 10 16GB SDHC cards at the time, but it has happened with Kingston brand cards in my earlier NXCAM.

See earlier threads for description of issue. Only difference is that, this time, camera did NOT recover the clip which was interrupted by the buffer overflow/crash, even though I asked it to.

Sony obviously envisioned a buffer overflow to be possible with this cam, hence the programming of a 'buffer overflow' message when it occurs, but they have not yet told me under which circumstances this was envisioned.

I hope to have something reported back soon -- meanwhile, has anyone else heard of anyone having this (really serious) problem with the cam?

I am feeling pretty hopeless about this issue now!

Adam

[Daniel Paquin]

Hello Adams,

It my sounds very weird what I will be saying.

From your previous thread, I read you are not located in the States but in South-Africa.

Do you have your GPS turned on, on your camera ? If so, is it possible the camera is trying to get the XY coordinate of your current location and that it does impact the capability of the camera?

Just a thought!

I find you current problems very weird, especially after changing the camera and the FMU unit. There is something else happening.

What are all the setups you have on your camera which are currently turned on.

Overflow messages happend on computers. Unless I am wrong this camera has some kind of computer. If you have an overflow something being activated "court-circuite" the camera functionality.

[Dave Blackhurst]

I know it's an entirely different camera, but I was testing a lower end Sandisk card (I usually use the ultra II or Video HD cards, this one is just the "base" model) in a Sony CX500V, and a minute in, I'd get the buffer overflow message, the "recovering file" message, and it would return to the standby state... I presumed the problem was the lower grade card, although another similar grade Sandisk card with higher capacity ran without problems - very likely it had later/better memory chips in it...

I lowered the bitrate (chose a lesser quality recording option), and the card that had been giving the error worked just fine, no errors.


You mentioned that Sony sent you some cards for use with the camera, do they work OK?

If so, I'm going to again go back to there being a problem with the cards being unable to accept data at the rate the camera is "feeding" it to the card. Basically the buffer in the cam is filling up with data and unable to write to the card fast enough to keep from "overflowing", at which point it stops, to prevent data loss.

I remember Tom's hardware did some tests on memory cards a while back, and there was quite a lot of variation between brands/grades - not all cards met the advertised specs either IIRC.

I'm going to venture a guess that you need 10-20% ACTUAL write speed overhead in the card to maintain max bitrate from the camera, and if the margin is too tight, you'll hit the wall. I'm sure if the bitrate is variable, that adds to the "fun" of trying to calculate the write speed required as well.

I'm not sure how you'd check the write speed of your cards, but there's probably a utility out there somewhere that you could use with your computer and a card reader?

[Adam Welz]

in answer to some questions:

1) My first cam buffer-overflowed and crashed in the USA in places where the GPS could not fix on satellites (in the NY subway) AND above ground. The new cam is crashing in South Africa because I'm working on a project here now. I doubt it has anything to do with my location north or south of the equator, but there is a tiny chance it might be triggered by the cam losing a GPS signal after having had one at the start of a shooting session or clip, as, come to think of it, the two recent crashes have come when shooting with a roof over my head -- in one case from within a car and another in a tin-roofed lean-to, both situations where GPS access can be iffy.

2) I have been using SanDisk Class 10 cards during most crashes. Before the most recent crash, I had used the exact same cards to shoot about 5 hours of footage (dumping and erasing a few times) with no incident. One would think that if the problem was simply that cards were too slow, this would happen virtually every time you shot a clip, or perhaps every time you shot a long, complex clip -- but I have shot many long, complex clips with no problem. The issue happens out of the blue usually during clips of less than one minute.

3) re the experience with another cam, one of the scary things about my NXCAM experiences is that, in every case, the cam has not registered a buffer overflow and returned to a standby state. It has registered a buffer overflow, then gone to a black screen with the words "Recovering data." and then frozen up entirely in a deep crash -- in other words, it is unable to recover from a buffer overflow, which seems to be a programming/design fault on Sony's part. I can only get the cam out of the deep crash by removing the battery -- it does not even respond to the power on/off switch being turned off.

I still can't believe I'm the only person experiencing this!!!

Adam

[Ron Evans]

I have never switched the GPS on with my NX5U. I have the XR500 for family stuff so its the only one with the GPS turned on. I will try later today inside the house running the NX5U with the GPS on recording to the FMU and the Patriot class10 32G card I have.

Ron Evans

[Ron Evans]

I recorded for about 1 hour and 30 mins with GPS on, OIS Active on, Peaking and Zebra on, first on full auto then on full manual. Starting outside ( it took about 2 mins for GPS to get a fix) then walking around outside, then indoors, down in the basement etc. Most handheld some just sat on a table recording my plasma TV on HD channel. All without stopping the camera, a single clip. Audio was PCM from internal mic auto level. No problems recording to FMU and Patriot 32G Class 10 SDHC card.

Ron Evans

[Gregory Barringer]

Does this camera have the World Com upgrade?

[Dave Blackhurst]

Well, I'm stumped...

On the CX500, I can reliably reproduce the fault with the card/buffer overflow, and it recovers gracefully... relatively. SO, based on your details... I'm stumped.

Sounds like it shouldn't be the cards, yet obviously SOMETHING is causing a data logjam or overflow under a specific set of conditions. Reproducing it with two cameras would now shift suspicion back to the camera/firmware.

Since there don't seem to be other reports (at least so far), somehow you'll need to figure out exactly what variables are involved when the failure occurs - you've got a failure mode "identified", but figuring out the exact cause may prove interesting. Ain't technology grand?

[Russ Johnson]

This may be cynical, but maybe this is Sony's way of saying you need to use their media. Have you tried Memory Stick PRO Duo media?

RJ

[Adam Welz]

1) Yes, this replacement camera has the WorldCam upgrade. But the same problem happened with the first one before it got the upgrade. The problem has thus happened while shooting 1080/25p and 1080/30p.

2) Sony gave me one 16GB MemoryStick Pro Duo card, but I need at least 2 to do the shooting I do. There was an offer for a second one but I have yet to see it. I refuse to buy one if they advertise SDHC cards as being OK!

Cheers

Adam

[David Mowbray]

It has been more than a month since the flurry of posts on this camera crash problem. Is there any update either from Sony or from your experience? I am considering the NXCAM but of course am now being more cautious.

....oops... please ignore. I just saw the other, more up-to-date thread.

Cheers
David

[Daniel Holoubek]

Hi David,

Could you please direct me to what post you are talking about...the one that states what Sony might be doing about an upgrade, I can't seem to find it. Thanks.

[David Mowbray]

Daniel... thanks but I realized (edited the post) that the up-to-date discussion was in another thread... and I was commenting on the difficulties that Adam Welz had been describing.

Cheers
David