Stuttering and VST Buzz

[ScottV]

I e-mailed jo@mutools before I knew there was a forum-- so let's try this again.

Here are two problems I'm getting. First off, when using MuLab in FullDuplex mode, playback stutters every couple of second or so. I've tried switching over to my MBOX and I didn't have any problems. Is this a known issue.

Also, when I try to put in a pluggin, let's say Auto Tune EFX, I get a buzzing sound. I open the plugin, click the green button to turn it off, turn it back on and the buzz is gone. Any ideas?

System:
XP SP3
Intel Core 2 @ 2Ghz
2 Gig Ram
MuLab Free (2.5.7)

Thanks,
s.

[pljones]

What soundcard and drivers are you using?

[ScottV]

Looks like my laptops (HP dv 9000) sound card is by Realtek with a Conexant High Definition Audio Driver (3.26.0.50), but I'm also using a MBOX with a digi32 driver (8.0.0.314).

As I mentioned, the stuttering doesn't occur with the MBOX. But VST static does in both. I've also tried changing the buffer rate when using the Realtek with no success.

[MuTools]

I assume you use ASIO4ALL for the RealTek.

If the stuttering only comes when using the Asio4All+Realtek, the problem must be in that section. I'm not an Asio4All+Realtek specialist but maybe a google about it could help?

The other issue: A buzz sound when using plugins like Auto Tune EFX.

Is that buzz sound coming with ALL VST plugins?

[ScottV]

Thanks for the reply.

The ASIO driver I'm using is "ASIO DirectX Full Duplex".

Looks like Auto Tune EFX is the one plugin that I'm able to find this issue in. Sometimes instead of noise, one channel is cut off but, again, when I turn the plugin off and on again... it works fine. Which is why it makes me feel like it's a host issue.

[pljones]

If it depends on the ASIO driver, like you said (i.e. it works one way with the Realtek and a different way with the MBOX), it's likely to be the ASIO driver. "ASIO DirectX Full Duplex" sounds like a layer on top of "DirectX" -- i.e. not native hardware ASIO support. That's likely to be where the problem lies. If you can adjust the audio buffer sizes (click "ASIO Control Panel" from MU.LAB's Audio Setup), try making them bigger.

[MuTools]

Looks like Auto Tune EFX is the one plugin that I'm able to find this issue in. Sometimes instead of noise, one channel is cut off but, again, when I turn the plugin off and on again... it works fine. Which is why it makes me feel like it's a host issue.

Turning OFF-ON the process switch in MU.LAB also 'resets' the vst plugin itself. (i.e. 'effMainsChanged' off-on).

If AT is the only plug i assume it's a AT buffer initialization issue.

If it would be a MU.LAB issue, it would occur with other plugs too, right?

[ScottV]

Everytime I try to post a follow-up message I get that my post sounds "spammy" so it won't let me post... so I'm going to post in parts to see if that changes anything.

[ScottV]

What you say sounds valid but I've tried Efx on other hosts through their demo's and didn't have any issues. I was just seeing if it was something that could be looked at.

[ScottV]

I don't really want to go back and forth between software designers and get the old 'point the finger to someone else' story. Not saying that you are. It's just not THAT important to me.

BTW, I did try changing the buffer and had no luck. I'll try updating the driver to see what happens. I'll keep this thread updated on the outcome.

[MuTools]

I've downloaded Antares Auto Tune EFX demo and tried it in MU.LAB.

And yes i got the same issue as you reported.

Unfortunately Auto Tune EFX doesn't allow the use of a debugger so i cannot research this efficiently. (did some rough realtime logging but that didn't reveal anything)

So i've emailed Antares about all this.

Hope they'll respond.