FIX: iZotope RX8 The selected audio device cannot be opened.

The selected audio device cannot be opened. Please make sure it’s not in use by another application and its drivers are up to date. (CAD 0x6E6F7065 [0x6])

Getting this error? If so, you probably can’t play back your file. The problem might not be the output device, but the input device you have selected.

The Fix

1. Open the Preferences for RX and select the Audio tab (if it is not already selected).
2. Under the “Input device” field choose a different device than what is currently set. “No audio device” worked for me.
3. Click OK to close Preferences.
4. Try playing back your file. If that doesn’t work, try another device.

Let me know if that worked for you.

Focusrite Liquid Saffire 56 Power Supply Unit Fix

A friend of mine brought over his Focusrite Liquid Saffire 56 audio interface to have me look at it. The unit wasn’t working. After turning on the power switch a few LEDs would blink and an internal relay would continually click, but it wouldn’t power on fully and wasn’t recognized by the computer.

We opened up the chassis and tried powering it on. WARNING: THIS IS REEEEAALLY DANGEROUS. DO NOT ATTEMPT UNLESS YOU KNOW WHAT YOU ARE DOING! We looked around to see if we could spot anything suspect. There were no obvious culprits like burn marks on the PCBs, blown fuses, or exploded/leaking capacitors.

Given the symptoms, I suspected that some of the electrolytic capacitors in the PSU were dried up or had vented—a common problem in gear that has aged a few years. Bad caps in the PSU could cause the unit to be under- or over-powered, which probably was causing the relay to keep tripping and preventing the main board from fully booting. After I pulled out the PSU I could more clearly see that the largest cap was bulged on top. That probably was the problem component.

Electrolytic capacitors go bad over time. At least one cap on this board had failed—perhaps others had failed too.

Since the interface was about a decade old and discontinued from manufacturing, it was essentially out of warranty. We decided to try fixing it ourselves.

The new PSU has a cool new look and maybe some better electrical engineering too.

I found a suitable replacement PSU sold by Full Compass. This replacement PSU doesn’t look the same as the original PSU that comes in the Liquid Saffire 56 and the Liquid Saffire 56 is not specifically listed as one of the compatible units, but it is in fact compatible. A Focusrite support representative confirmed that this PSU is the correct replacement.

So my friend ordered the PSU. A few days later it arrived and I swapped the old for the new. The interface fired right up and is working like new.

It’s working!

FIX: Pro Tools “Could not create a new document because Assertion in…”

The Problem

Could not create a new document because Assertion in “/Volumes/Development/223020/ProTools/DFW/Views/UMenu.MacOS.mm”, line 1813. (Use the Copy button to copy this message to the clipboard.).

Pro Tools 2018 error

If you get this error, it’s likely due to Pro Tools trying to use the wrong audio interface.

The Fix

1. Quit Pro Tools. (Not forever, just for a moment.)
2. Restart Pro Tools while holding the ‘N’ key. This forces Pro Tools to ask you which interface to use.
3. Select your interface.
4. Boom. No more error, hopefully.

Caveat Emptor

This worked for me on a Mac Pro trashcan running macOS High Sierra 10.13.6 and Pro Tools 2018.7.0 on a Tuesday in November. The Moon phase was Waning Crescent. I had vegetable soup for lunch and was facing South at the time of the error. Your mileage may vary.