Audio crackles

Good morning all, could someone possibly please help as I have a niggly problem that’s driving me mad.

I have just bought an iMac (spec below) and installed Cubase Elements 7. I am up to date with all drivers and have the latest OSX (Mavericks) installed. My hardware is an M-audio Fast track ultra 8R 8 channel USB interface.

It all works lovely, apart from every now and then, totally at random, I get a burst of crackles for possibly half a second or so, once every few minutes.

This is not affected by processor load, buffer size, or graphic load (still does it with the screen minimised). I’ve turned off wireless connectivity with no effect. I would turn bluetooth off but I daren’t in case I lose my mouse and keyboard and can’t get back in to change it.

I have checked all mains connections to outboard equipment just to be sure. I can play CD’s and MP3’s etc all day with not a crackle in sight. I’ve also noticed that if I have heavy reverb selected, the crackle also has reverb on it which would suggest it’s the input side of things rather than the output.

The processor load, depending on buffer size, is at worse about 15%, at best 5%. Even at silly buffer sizes in either direction it makes no difference to the crackle.

Is there anything in the OSX setup I can alter to prioritise resources to Cubase? I’ve tried running after a cold start with no other software running with no change, and I’ve tried it with mail and Safari running in the background with no change.

I’ve tried changing Audio priority to boost, turned off multi processing and ASIO guard, and turned off adjust for record latency. I’ve tried different sample rates and bit rates.

Any ideas? It’s bound to be a daft check box I’ve missed somewhere!

Does anyone have any settings to optimise my iMac for Cubase use? I’ve read loads of articles that are ambiguous, but surely there must be one prime setting for my machine? And yes, I’m running Elements 7 64 bit, version 7.0.6 build 2231.

I’d like to run it at the maximum quality my hardware allows (96Khz 32bit) with the best buffer size I can get away with.

It’s worth pointing out this crackle happens when I’m just playing through, not even recording, so I don’t think it’s disk related. The bar graph doesn’t even move for the HDD even when recording and playing back several channels at once.

It works beautifully apart from this annoying crackle. Can anyone help, please?



I have seen other people having similar problems with their brand new Macs which is really frustrating.
Turns out the problem lies in the new Mac models’ USB 3 port. These USB 3 ports are not completely backward compatible with USB 2.
The solution would be getting a USB 2 hub (preferably powered), so that your devices are connected to your Mac indirectly and through the hub. To be on the safe side, even connect your dongle to the hub.

Hope this helps.

Worth a try! Thanks ipanema :slight_smile:

Well, finally got round to getting a powered USB 2 hub today, plugged it in and gave it a whirl. Dang it, the crackles are still there. I’m reduced to yelling obscenities at it now! Any ideas anyone, please?

So sorry about your frustration.
Another thing I can think of is that the driver for your audio interface may not be quite compatible with Mavericks. I searched the M-Audio website, and surprisingly found no trace of Fast Track Ultra 8R itself, let alone the latest driver for it. AFAIK, M-Audio haven’t released any driver for Mavericks for any of their products yet. Typical, they are always late when it comes to releasing new drivers.

Assuming you had been using your Fast Track before your new iMac, did it use to work properly under an older OS version?

Thanks for trying to help Ipanema. M audio sold the rights to the fast track to Avid, and they have kept the drivers up to date. Having said that, I’ve just looked again and they say OSX 10.9 is supported but currently not 10.9.1, which typically is what I’m running, d’oh!Hopefully, if it is a recognised issue, they will release a driver in the near future. I wish I’d stayed with Mountain Lion! I’ll just have to live with it for now I guess. The Fast Track works fine on my Windows 7 laptop, so there’s nothing wrong with the hardware.

Thanks for your efforts, hopefully a new driver is on the way!


I’ve finally sorted this out. I partitioned the hard drive, and on the other half installed Mountain Lion (OS X 10.8.5) and re-installed my audio hardware and Cubase 7. Works perfectly now, and I can boot up to my old set up still so it’s like two computers in one. Some boffins don’t like the idea of two operating systems on one hard drive, but it works perfectly for me. And I can use my existing projects and audio folders on the other half of the hard drive. Oooosh!

And thanks for the info. So it WAS a driver problem.

About having 2 OS’s on the same drive, don’t worry at all. I always have more than one OS on different partitions on my main drive, sometimes even three! This way I can test new drivers or software. So it’s basically a good idea, and you did great in trouble-shooting that driver problem.

Good luck.

Thanks mate :slight_smile:

if apple keeps up this idiotic policy of new OS every 6 months and NOT backwards compatible its already going to alienate alot of developers. when they bring out the new “sandbox” architecture NONE of your old plugs will work requiring developers to rewrite them ALL. good luck with that apple brilliant move…LMFAO