Audio distortion using USB Interface in Cubase 6

Having a peculiar issue, and have done various troubleshooting to arrive at a Cubase 6 issue.

Playback and recording is absolutely trashed when using a USB Interface. Tried Audacity, recording and playback is smooth. Ran an installation disk of Cool Edit Pro I’ve had for well over a decade in Crossover. Even IT understood my Aggregate Device and was able to record and playback properly!!

Curious if Cubase itself was the issue, I installed the free trial for Cubase Pro 9 in an attempt to single out a software hiccup, and everything worked smoothly. It’s just Cubase 6 that it doesn’t like.

I’ve experimented with buffer sizes, different interfaces (Yeti USB Microphone, Focusrite Scarlett 2i4), and the only thing I’ve found is that the built-in headphone jack and mic work flawlessly with Cubase 6. When using an Aggregate Device or just the USB ASIO driver, it produces the issue in the video below:

Also potentially worth noting:
-Whatever interface I use get completely crashed by Cubase 6. I have to quit the program, unplug, and replug my interface.
-My same license for Cubase 6 also works on my Windows 7 and Windows 10 machines, whose hardware specs are far worse (first generation i7-870!).
-I’ve tried every USB port already, have not tried a powered USB Hub.

Thanks for your help!

Start by using a supported OS.

Good evening at all …
Sorry but I use the google translator!

I too have the same problem:
MacBook Air (13 inches, beginning of 2015)
OsX El Capitan 10.11 … 5
Cubase 6.5.5
focusrite scarlett 2i4 (new)

I would like to avoid upgrading to 9, rather than changing sound card!

Thank you and soon,

Hi, Roberto.

I’ve not had any luck resolving this issue through any route. I can only assume Apple changed something somewhere along the line with how playback and recording is handled. I found an old DVD I made of Mountain Lion years ago. I’m going to attempt taking a Carbon Copy Clone of my hard drive, wiping it, and trying to install an old OS just to use Cubase 6. It’s very frustrating. I have a layout that I’m very used to and am not ready to upgrade. I’ll report back with any findings I have.