Topic: Workaround for AIO activity-related hiss and noise problem

Hello, RME!

I wrote about my issue already. I have 8x2.26 Mac Pro and first series AIO, modified by soldering by official dealer. Despite of modifying, there are very annoying HDD/CPU/GPU-activity noises and hisses.

Very good warkaround was proposed in this forum (http://www.rme-audio.de/forum/viewtopic.php?id=6944), but it seems it is impossible on Apple hardware (due to closed EFI).

It seems that problem somehow related to new processor energy saving options. May be noise surge appears due to voltage ripples then Nehalem tryes to lower (and raise back) power consumption (when CPU load less than 100%).
Also I am wondering if hyperthreading affects it.

I noticed that noise and hiss sometimes disappears (for example at most boot time or when shut down dialog displaying or sometimes for 1 second just without reason). So I started to searh for various applications be able to do some CPU tasks for this result. First I noticed that if I start Plex player noise greatly reduces (althought not dissapears completly), but this is working only when any output of internal soundcard is selected in Plex preferences. So proposed workaround is to run Plex at background (it is not requiring to play something, just enough to stay in menu) and working in Logic.

I am not sure 100%, but it seems many (if not all) other applications using internal soundcard produce such effect. For example it is working to set any output of internal soundcard as default in System Preferences, start browser (Safary and Opera tested), load any video at youtube.com and start playing (and pause it). But some noises are generated all the same due to flash animation.

RME, can you research this workaround, find some dependences and to implement it at drivers as, for example, some CPU tasks or using internal soundcard (if it is required) or something? Or may be it is able to tweak processor halt modes from Mac OS X?

Re: Workaround for AIO activity-related hiss and noise problem

I got the same issue with win7 and Fireface 800.
maybe sounds like this? : http://www.youtube.com/watch?v=nuqtU7u_ … re=related

Re: Workaround for AIO activity-related hiss and noise problem

Randay wrote:

maybe sounds like this? : http://www.youtube.com/watch?v=nuqtU7u_ … re=related

No, It is like in this video:
http://www.youtube.com/watch?v=XUk7NJDT9vM
Note it occurs on such brand as Apple Mac Pro (2009 base stock octo), and I think that RME have to test such config as it often used by pro audio users.
I am wondering why RME ignores my messages in forum except message that on Daniel's PC all is ok.

Re: Workaround for AIO activity-related hiss and noise problem

Hello.
I have been getting many complaints on Gigabyte Motherboards from RME users, not only from Intel Based systems, but with Intel based systems the problems are far worse.
First, What Video card is this ?

5 (edited by blinkfrog 2010-02-04 08:05:54)

Re: Workaround for AIO activity-related hiss and noise problem

Byt3 wrote:

I have been getting many complaints on Gigabyte Motherboards from RME users, not only from Intel Based systems, but with Intel based systems the problems are far worse.
First, What Video card is this ?

Youtube video isn't mine. I have a stock 8x2.26 Mac Pro with nVidia GT120 videocard. If other videocard can resolve the problem I would upgrade videocard.

P. S. Also I have assumption why my workaround have an effect. There is info that using internal soundcard leads to rise of the CPU temp, so may be this bug somehow disallow CPU to use energy saving states (may be switching in this modes like c1e produces these strange noises).

P. P. S. Indeed, I have found some posts with info that replacing videocard by other brand can solve the problem. But Apple videocards are not cheap, so I need 100% certainty that it can help. So somebody have to do the tests with Mac Pro. I think, RME have to.

Re: Workaround for AIO activity-related hiss and noise problem

After installing Apple Mac Pro 2009 Audio Update 1.0 proposed workaround isn't working anymore.