View Full Version : Sudden crackling / distortion in audio through USB interface

08-10-2016, 03:20 AM

I use a late 2015 Retina iMac, which is connected to a Yamaha AG06 USB interface. The interface provides sound output to my studio monitors.

For the past few months, audio has been working flawlessly, but all of a sudden yesterday things went awry. Audio works briefly (often less than 30 seconds) and then crackling / distortion occurs, eventually leading to audio fading out and back in. The is resolved temporarily if I turn off the interface and turn it back on. I have not altered any settings or installed new applications - the issue simply appeared out of nowhere. At first I assumed it was the fault of the USB interface itself, but I have tested it on another Mac and it is working with no issues. I have tried restarting, shutting down, uninstalling all additional audio peripherals and unplugging all other USB devices, but the issue is still there. I have tested other USB peripherals, including a Schiit Audio USB DAC, and all is well.

Has anyone experienced this issue before? Any ideas what could be the cause?

Any insight is highly appreciated!


08-10-2016, 12:32 PM
I'm probably teaching grandmother to suck eggs here, but I'll offer my own troubleshooting steps just in case.

First off, it sounds like you've checked the hardware, but did you check your cables?

You could also have a look in Preferences/sound and try adjusting the volume being fed to the Yamaha. I doubt there are any further controls.

Is the problem on both channels, or just one? If it's both, I'd revisit the hardware.

Do you have any equipment that will take a different connection method, such as a DAC?

Last but not least, the USB connection is 2-way. Are you sending anything from the mixer to the computer that may be confusing it?

From AudioFanzine:

"One interesting feature on the AG03/AG06 is the To PC switch that allows for choosing which inputs will be sent to the computer or iOS device. The Dry Ch 1-2 allows for recording inputs 1 and 2, Input Mix sends all the inputs to the USB stereo port along with the USB return from the computer, which allows for mixing the mics and instruments to music, add effects from the computer and more."

08-13-2016, 01:06 PM
I'm probably teaching grandmother to suck eggs here, but I'll offer my own troubleshooting steps just in case.


Kinda wondered, after I replied with some help, never heard back on any of them.

08-13-2016, 01:21 PM

Kinda wondered, after I replied with some help, never heard back on any of them.

It's the nature of forums. Sometimes you hear back and might even find out whether your fix worked. Often, you don't, and never know whether the OP ever revisited his thread.

Best bet is to press on regardless. You never know how many people your advice might help, and researching problems helps us understand our own equipment better.

08-13-2016, 05:44 PM
True. But it's helpful to post back if something helped.

It's a tough subject, god knows the issues I've run into with my insane recording setup! Audio can be so finicky! One reason why I'm still running Yosemite! I'm only now peering at El Capatain before the next one comes out (and avid and others say don't upgrade!!!!)

08-13-2016, 05:46 PM
BTW nice reel to reel in your pic. I'm fully digital but would love to find a deal on a half track someday, even though I do have some UAD tape simulations which are awesome.

08-13-2016, 06:18 PM
I have a few of them. That's my favourite and the only 10" machine I have. The others are all 7" of various types.

There's something cool about analogue. You can actually see something happening rather than just a HDD light flickering.

08-13-2016, 07:27 PM
Nice. Are they all 2 track (stereo) or any 4 or 8 track? I see the odd fostex R8s go on kijiji but they seem overpriced to me, and the tape isn't wide enough imo. I have 16 mic pres, UAD apollos but I do have one nice set of analogue pres I send into the line ins, an API 3124 rack of 4 discrete API 312s. The UAD unison lets me run Neve strips and it's quite close.

But I am from a time where full neve boards, 24 track 2" machines, I miss the woop! woop! whoop... wooooooop of the rewind and slow down sounds of the 2" machine is gravely missed. The racks cost me a mint as did the mics, when I recover I'd love to slowly snag some more analogue gear. There's enough of it floating around. Visions of a sweet deal on a pultec eq, or a fairchild compressor floats in my head someday!

08-13-2016, 07:39 PM
Mine are all stereo. I know what you mean about prices. There's something of an analogue revival at the moment and items that would have been landfill a few years ago are fetching serious money.

There's a Fostex on CanuckAudioMart for $500. Looks to be in good shape.

08-13-2016, 07:48 PM
500 seems more reasonable. But, for me to see real benefits over the UAD tape stuff, the tape needs to be wide. And costs serious money right now. Maybe a nice 4 track machine or just a simple half track would be nice. But everyone and their brother is hunting for those so I'd need to get lucky on someone I know snagging me a deal. For now I'm keeping my eyes open for more good drum mics. The ones I got have already cost a mint! (shoulda been a guitar player... a simple 421 woulda sufficed!)