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How to resolve "underflow" issues with Pro Tools

Joined
Jun 28, 2013
Messages
92
Motherboard
ASUS ROG STRIX Z370-H GAMING
CPU
i3-8350K
Graphics
RX 580
Mac
iMac, MacBook Air, Mac Pro
Mobile Phone
iOS
I'm using Pro Tools 12.6 with my Hackintosh, connected to a Digi 002 control surface via FireWire 400. Everything on the Hackintosh was working perfectly, until I tried to use the "Avid 002" interface.

Any playback at all would result in a data "underflow" error, with the suggestion of DECREASING my buffer size, which was unfortunately already at its lowest value (32 samples).

I found a very simple fix here. In summary:

1) Launch the Audio Midi setup app (in the Utilities folder)
2) Select Pro Tools Aggregate I/O
3) Uncheck all audio devices EXCEPT the Avid 002
4) In Pro Tools, Setup/Playback Engine, select Pro Tools Aggregate I/O

Voila. My rig now supports the legacy Digi 002 control surface without a hitch.

UPDATE: Although using Pro Tools Aggregate I/O worked, I had to manually toggle between Avid 002 and Pro Tools Aggregate to get the Digi 002 control surface to connect to the session.

In solving a (seemingly) unrelated issue, which was losing Ethernet and front panel USB 3 connectivity after sleep, now everything WORKS in Pro Tools, WITHOUT using Aggregate. I simply connect to Avid 002, and sessions open up and connect to the Digi 002 just fine.

So what did I do? I removed the AppleIntelE1000e.kext from Library/Extensions, and installed instead the IntelMausiEthernet.kext extension in its place (using MultiBeast). It would appear that this networking issue spilled over into the FireWire world, causing the underflow issue.

I am using a FireWire "Syba Low Profile PCI-Express 1394b/1394a (2B1A) Card, TI Chipset, Extra Regular Bracket SD-PEX30009" available on Amazon. Sitting at 32 samples latency and the system isn't even breathing hard with MANY plugins and tracks.

I am VERY happy.
 
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