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Anyone else had issues with VDAT deciding to deliver 0dbFS white noise at random?

Hit play - sweet, hit rewind and then play and if our lucky you won't be hanging from the ceiling.

My nerves are shot

Any help appreciated.

Simon

ps the real bummer is it sounds better than the mix I'm working on

grappa wrote:ps the real bummer is it sounds better than the mix I'm working on

I don't think they charge extra for that

I don't really remember - maybe this is the problem, that goes away when recording 32 bit? Or was the the GraphiqEq?

I'll have a go on a test project at 32 bit and see if that makes any difference.

I notice in a search you bought a BRC - did you get it working with VDAT?

Simon

No, my BRC doesn't work with VDAT. The thing is, that when I use locate points. It locates the right point, but when I then hit record or play, it jumps to the last position and continues from there. This is really useless.

However, my BRC comes with firmware version 1.03, and atleast 2.03 is needed for it to work with the Alesis HD24. I am trying to find a place that can do the upgrade for me, since a change of hardware is needed to do this.

I use VDAT with 16bit files - my external converter is 16bit and had a full scale glitch at the beginning of the record (for the first time ever btw) yesterday.
My system frequently lost sync whenever tasks which would be supposed to cause an increased interupt rate had to be performed, like dragging a device or window over the screen, acessing the disk etc.

I was pretty sure it was a mechanical problem as one pair of Adat connectors (too thick) didn't fit well through the slot outlet and probably had displaced the card.
After re-seating and tightening the screws again the problem was solved.
I guess the interupt line of the main card had (partly?) lost contact.
Not sure if it's similiar in your case, but it's worth checking - together with the interupt configuration of the system.

cheers, Tom

Thanks Tom,

I do think my system needs a review as I am getting some audio generated from graphics redraw etc and believe that this can be an interrupt issue.

Simon

yes, that's correct. It seems to happen even without obvious irq conflicts, as I remember I had something like that on a system and solved it by a simple re-install.
I remember it so well because I assumed the powersupply was too weak (after all it was labeled 110 Watt...), but things aren't always what they look like
Anyway, I have no idea about the source or what exactly cured it - I did the same install procedure as before, strange.

cheers, Tom

There's a tool here called DPC Latency Checker:
http://www.thesycon.de/eng/free_download.shtml

Run it for a while and see if you can see the interrupt issue showing up... This tool can help you tweak various things and see the effect quite easily (rather than having to run VDAT and wait for hte problem to reappear). That is assuming it shows the issue to begin with. Anything OS related or running in the background will definately show up.

Took the bull by the horns and removed my cards over the weekend.

Disabled everything in the BIOS that I can, removed redundant cards and re-installed.

No shared IRQ's now.

My glitches seem to have disappeard with VDAT but I am still getting low level noise generated when I drag icons on screen. It's an integrated gfx controller - would that make a difference?

I also hear very low level noise when the system is running (so low in fact that a real signal would probably pop my eardrums - I am carefull!) - I have disconnected all hardware that I can i.e. monitor etc but it is still present? Sounds like a sort of ticking sound in amongst the noise?

I will try the Latency checker and see what it throws up.

Appreciate the help.

Simon

integrated graphics!!???
horrors.
integrated graphics means memory and other resources needed for graphics are shared with the rest of the system. an agp or pci-e graphics card should help a lot(not a pci card!), if you have such a slot available in your computer. if not, eventually you'll want to build a new machine.

this may add to the picture as my VDAT recently really misbehaved... which it hadn't done before, a since I hadn't had much time to use it anyway, it didn't really matter)

my Scope system boots from a (quality) flashdisk, that's plugged directly into the IDE connector - that thingy was a hell of expensive, but performs excellent.
2 nd drive was a regular harddisk, but I replaced it with a compact/flash to IDE adapter. Basically no problem, but it performed noticably slower than the first drive.
Impossible to record with VDAT to the compactflash card, lost synch, wierd reactions etc. Strangely it refused to work with the main drive, too (which it had once done).

A look into device manager revealed that the compact flash adapter was listed as an int-13 device, so it ran in PIO mode - which is supposed to drag the other channel's performance down... (I I remember correctly)
Removed the adapter - VDAT seems to perform radically better.

My conclusion is that whenever VDAT doesn't get it's access to disk immediately (by whatever reason), it starts bitching around.
I don't think it will make friendship with a disk-streaming sampler accessing the same drive, for example...

cheers, Tom