Logic Pro 7.1 - UAD-1 Cards causing stuttering

[thewitt]

This is a multi part question. Thanks in advance for reading and any input.

Here's my set-up
G5 DP 1.8 1.25Gb RAM (4 RAM Slots)
RME FF 800
LP 7.1
OSX 10.3.9
Pro App Support 3 installed
3 X UAD-1 Cards Installed (Latest Software 3.9 I believe)

When I'm starting and stopping playback, it works fine, then sometimes (1 out of three) starts stuttering and sounding like the wrong sample rate. Then ( I was right) I get errors \"Unable to synchronize audio and midi\" and \"Sample rate 39035 recognized, check conflict between Logic and external devices\". If I let it play, sometimes it straightens itself out...

I tried this with the FF800 off (using the G5's audio out driver) and still got the same result.

I then discovered that removing a UAD plug from an Audio Instrument channel stoped the initial problem.

But then placing LP in record mode would replicate the problem (every time you start play, recording or not). This could be solved by removing (bypassing) the Plate 140 Reverb that is located on a Bus. But the order must be: Bypass 140, then arm track for recording.

In Logic, I have the Prefs> Audio> Drives> Core Audio settign as:
I/O BUffer Size: 64 (Also tried 128)
Universal Track Mode Checked
24 Bit Recording (session at 48K)
Software Monitoring Checked
Process Buffer Range: Small

What settings should I be using for LP and UAD-1 Cards?

Now, this is new since installing the UAD-1 Cards a couple of days ago. Is it the fault of the cards (faulty hardware)?

How do I know if I have an AMD-8131 chipset and could this be the problem? (I looked at all the links off the Uaudio site and though they claim to list specs on linked pages for Dual 1.8s, there are only listings for SINGLE 1.8s)

What should the MIN_GNT be set at?

 

[mersisblue]

raise the buffer to 256 or higher when mixing

I have the same setup on a g4 . Is there a masterlink or cd burner or SOMETHING connected digitally with the wrong sample rate ?

have you opened up the fireface settings app to check the sample rate

clock mode etc... ?
I also dont have the 140 in logic ...... try rmoving that one plugin does it still happen ?

 

[johnmccaig]

yah the uad-1 card doesn't like that low of a buffer..
i have mine as high as possible when not tracking.. and if i need to track with UAD-1, i make sure that nothing else is taking too much native CPU power.

 

[thewitt]

Thanks for the replies guys.

>raise the buffer to 256 or higher when mixing

I don't have a problem when mixing. Only in Record Mode.

>I have the same setup on a g4 . Is there a masterlink or cd burner or
>SOMETHING connected digitally with the wrong sample rate ?

No. Just the FF800

>have you opened up the fireface settings app to check the sample rate
>clock mode etc... ?

Yes. Do you have recomendations for the FF 800 settings?

>I also dont have the 140 in logic ...... try rmoving that one plugin does it
>still happen?

As stated, bypassing or removing the Plate 140 solves the problem.

>yah the uad-1 card doesn't like that low of a buffer..
>i have mine as high as possible when not tracking..

\"High as possible\" is definitially too high. Also, the problem is when tracking (recording), not mixing.

>and if i need to track with UAD-1, i make sure that nothing else is taking
>too much native CPU power.

No problem there. Just LP7.1 and Reason 2.5 running.