clipping sound on new iMac when Logix X is running

I just got the new iMac that was released two weeks ago yesterday. All I did was set it up with Logic X, Main Stage, and Aperture all from the app store. nothing else was put on it. I opened up logic just to check it out and see how much faster the performance would be. I just wanted to give it a quick test and played some apple loops I immideatly noticed it was making a clipping sound randomly. The meters were not peaking everything was in the green and if you turned down the gain the clipping just got quiteter. I called apple support thinking it was a hardware issue. They had me do some trouble shooting like playing the same loops through quicktime and the clipping persisted. they also had me play a youtube video to see if I could hear the clipping. It wasn't as noticible but it was there. Apple decided that it would be a good idea to reformat the computer tomorrow and start over. Sounded fine to me seeing how I didn't have much installed yet. I did a little more trouble shooting on my own after I got off the phone with apple. First I made a copy of three apple loops and put them on my desktop then restarted the computer. Then after a fresh restart and nothing running I opened one of the apple loops off the desktop with quicktime player and it sounded great no clipping. Same with You Tube. I then opened Logic Pro X. Did nothing with it but minimize it. I then went back to quick time player and tried to play the loop again. This time the clipping was back. Same with You Tube.

My conclusion for some reason when logic is running the audio makes a random clipping sound no matter what audio program you play the audio through. (Clipping sound comes out of the internal speakers as well as headphones)

All of my software is up to date.


I am running:


27" iMac

3.5GHz Intel Core i7

16 GB 1600 MHz DDR3


If anybody has experienced this same problem or has any recomendations they would be greatly appreciated.

I am going to reformat in the morning and try and start again.

I will post my results


Thank you,


Aaron

iMac (27-inch, Late 2013), OS X Mountain Lion (10.8.5)

Posted on Oct 8, 2013 11:22 PM

Reply
998 replies

Nov 16, 2013 4:18 PM in response to jwweeks

After talking to general Apple support, Pro Apps support, and CPU support, I have to box up my computer and take it to the Apple store.


We tried the following:

-Startup in "Safe Mode"

-Clearing PRAM

-Startup after unplugging iMac power supply for 60 seconds

-Reproducing issue #1 in Garage Band

-Creating a "Test Account" to ensure it wasn't a user preference issue


And that's all I can remember off the top of my head. Also, it seems that the crackling, for me, is produced after using "Input Monitoring." Once that is initiated the crackling begins, even if you turn it off for subsequent recordsing. No, it's not a latency or buffer size issue.


I mentioned this thread and the potential FD issue to everyone I talked to, but none were familiar with it. I'll post back when I have updates.


Wish me luck!

Nov 16, 2013 4:24 PM in response to jwweeks

I am seriously thinking of taking my audio interface (Focusrite Pro 14 via thunderbolt to FireWire adapter) and a memory stick with one of my sessions from LPX into the Apple store and Trying THEIR 2013 3.5ghz i7 iMac and see what happens!?


Still have a "log/ticket" with apple that's been weeks now.

Sigh.


I think we should get the iMac's swapped out with 1TB SSD's for compensation.

Also can't believe that the new update won't solve this. How king is it gonna be now?!?!

Do I start billing Apple for the extra studio time cause my slow *** Old MBP can't keep up, hence the upgrade to the imac?!?!?!


Sigh.. So tired of this issue now. Want it fixed. Irony is if we all went with a 2012 iMac, we wouldn't have this issue!? Madness!

Nov 16, 2013 6:04 PM in response to Johnpaulmusic

No audio 95% of time from MOTU Traveler mk1.


Brand new iMac bought 5th November 2013.

3.5ghz.

3tb fusion drive.

Gtx780m.

Latest updates.

Mavericks.


Motu are aware of problem and apparently so are apple.

Motu doing best to figure out if it's a core audio problem (needs apple fix) or a firmware/driver update (Motu fix).


Speakers can scream with high pitch micro phonic type infinite sound which can be stopped by selecting or deselecting core audio control...temp fix fir like 2 seconds if at all.

Sound sometimes come back but totally unreliable.


If it's not fixed before start if December it's a refund (agreed with apple for 14 day return extension to 30 days).

Would rather it was fixed though.

Nov 16, 2013 7:07 PM in response to Johnpaulmusic

Just to clarify so there is no confusion here..........

Also can't believe that the new update won't solve this. How king is it gonna be now?!?!


Bear in mind what is being spoken about is just the latest seed and not the finished update... There is still time for the Engineering team to implement a fix.. be it part of this next 10.9 update or a separate firmware/software update for 2013 iMacs with FDs... that could be released prior to or after, the 10.9.1 update


Trying THEIR 2013 3.5ghz i7 iMac and see what happens!?


If it's one with an FD you will continue to have issues.. If it's 'sans FD' then it should be fine... One of my clients has the same interface using FW and with a FD-less iMac he has no issues... but feel free to try it out for yourself.


Irony is if we all went with a 2012 iMac, we wouldn't have this issue!? Madness!


Not exactly.. If you had gone with a 2013 iMac without a FD you would have been fine too given your audio interface uses Firewire... It's only those with USB interfaces that have issues with Mavericks and USB3 ports on newer Macs... due mainly to driver incompatibilities..

Nov 16, 2013 8:49 PM in response to jwweeks

jwweeks wrote:



the top of my head. Also, it seems that the crackling, for me, is produced after using "Input Monitoring." Once that is initiated the crackling begins, even if you turn it off for subsequent recordsing. No, it's not a latency or buffer size issue.


jrweeks,


I have a question:


What does your Mac have for input options?


If you go to Audio MIDI setup what input options do you show for audio. It's my understanding the new machines do not have a "Line Input" what about "digital input" or "mic input".


If you have both digital Input and Mic input do both of those show up in Logic?

Nov 16, 2013 9:02 PM in response to Pancenter

Hey Pancenter,


I know you had mentioned the line input going away in the new iMacs before. I discovered something the other day by accident I got a new set of headphones (sennheiser Momentum's). By chance I was wearing them when I was using logic and created a new track that was set to internal mic for the input but the Momentums come with a mic and volume control like iPhone EarPods. When they were plugged in it was grabbing the audio right from the headphones mic.


Does anybody know of a good cable that can break that jack out so you can use headphones and have a line in?


Thanks,


DeadPhish

Nov 16, 2013 9:38 PM in response to Deadphish42

DeadPhish,


That's the way most tablets are setup, so any of the iOS type audio interfaces should work, I wonder if it's possible that it's a stereo IN, probably just mono.

<edit> I should have said - iPhone/Tablet audio I/O devices that use the headphone port should work


My curiosity about Inputs types is because the (reported) Rice-Krispie crackling is indicative of an unlocked digital audio stream. I wanted to see what available inputs can be seen in Audio MIDI Setup. And to see if different Inputs, sampling rates or bit rates changed anything.

Nov 17, 2013 12:36 AM in response to Inkaroads

Actually, Inkaroads, you can have a perfectly functioning system. But you must be OK with buying a Belkin Thunderbolt Hub. Just plug your USB Duet in and start working! So far after a few days I've not had a single problem. And I've been working 16 hour days in multiple programs. My computer is an iMac 3.5GHz i7 16GB ram &amp; 3TB 7200 drive w/ USB Duet 2. The Belkin hub is $300 but I believe it's worth it. I highly recommend it as it bypasses any USB based problems. So if you don't mind the $300 you can purchase it on the apple store :)

Nov 17, 2013 6:28 AM in response to Wound

I realize that this doesn't really add to the discussion, but what bothers me is that so far I have seen no actual evidence whatsoever that Apple is working to fix this problem (ditto Apogee).


What's more, there seems to be wildly disparate treatment of new iMac buyers with respect to returns. For instance, some have been told that their return period will be extended to thirty days, while others (such as I) have been told firmly that the fourteen-day period (which I've missed) stays in effect. If the problem is the same, then treatment of the buyers should be the same.

Nov 17, 2013 6:33 AM in response to Wound

Wound,


Again to clarify...


The USB3 issue is differerent to the 2013 iMac with Fusion Drive issue


The FD issue can affect any audio interface.,.. FW or USB but only when used with a 2013 iMac with a FD fitted. This issue will require a fix from Apple.


The USB3 issue affects USB2 devices plugged into the USB3 ports of Macs of any type... This issue will require updated drivers and/or a firmware fix from the Developers of the USB2 Audio Interface.


Note: Owners of a USB2 Audio Interface and a 2013 iMac with a FD fitted could be subject to both problems!

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clipping sound on new iMac when Logix X is running

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