46 replies to this topic

[soundgardo]

ka0zzz, on Jan 6 2007, 02:10 AM, said:

i have the same problem, anyone solved this issue ( the speakers binding change in a random way ) ?

The same for me..

[xgportal]

Hi,

I've got another issue.

The guide works fine, but my sound keeps on dropping!!

Sometimes it works other times it don't Ive got that specific chipset on nforce4

ASUS P5N32 SLI SE Deluxe

any help please?

EDIT:

Ok, I found kind of a solution, hope this lasts:

I edited the Info.plist and saw there where multiple vendor id under Nvidia AC97, I removed all but the 59 one and rebooted, Now I have audio without drops.

Edited by xgportal, 16 February 2007 - 05:36 AM.

[AdamWe]

For me it shows that I don't even have devices

Anyone know how to fix this?

Edited by AdamWe, 16 February 2007 - 08:58 PM.

[Jhero]

What happens if you leave audio midi app launched? Does it still randomize the channels?

[xgportal]

No, it changes my config to 6 channels and then I have no audio, but I then put it back to 2 channels and all works.

[Donciakas]

The same sh**t for me. With asus A8N-SLI SE mobo and ALC850. It plays just 2 speaker configuration. When setting it to 6 speaker , also plays just 2 speakers after some more configuration choosing the right speaker. Don't know how to solve this problem, read many posts, but nothing....

[50875683]

i can not get it work!!!!!

[Download17]

Yeah... Nevermind this thread guys... sorry for the confusion... turns out it was VLC that was giving me the 5.1 configuration (only when playing certain videos) and I didn't even notice... dang...

[Fesob]

soundgardo, on Jan 29 2007, 02:47 PM, said:

The same for me..

The same for me too

[pandnaka]

I have a Abit bord with the same sound chip set but I have no sound at all!!! (ACL850)<<<---No sound help!!! Please

[Harley]

pandnaka, on Apr 6 2007, 05:04 AM, said:

No sound help!!! Please

Try one of those - http://wiki.osx86pro...tyDrivers#Audio

[covenant]

I have a DFI Lanparty with ALC 850... I have the multichannel option as presented here, and each speaker has the option of 6 channels. However all 6 channels only operate 4 of the speakers! Neither the center channel nor the subwoofer will output anything (these go to other channels when selected).

[Angel Bunny]

thank you!  

[ksh]

ka0zzz, on Jan 6 2007, 12:10 AM, said:

i have the same problem, anyone solved this issue ( the speakers binding change in a random way ) ?

another one with the same problem. still no fix ?

[covenant]

I guess ALC850 users are never going to have a fix then... the 5.1 setup method described in this thread was close, but no cigar. The speaker assignments switch randomly. Sometimes you can't even complete the configuration without it changing output channels that you've already configured and you go in a circle "chasing" the correct settings as they keep changing. Sometimes, you can get it set right for a while, then it stops whenver you start/stop iTunes or Quicktime.

[Wenle Z.]

anyway to get the ALC882 working with 5.1??

[kaid]

Okay, I have an Asus A8N-E with ALC850, too, and I think I know what the problem is:
The ALC850 actually has 8-channel, not just 6-channel! So every time it is accessed using 6-channel output, there's two "ignored" channels "left" and hence the output channels are rotated by 2!
Try it with some AC3 testfile in VLC. Every time you play it, it shifts 2 channels, there are 3 different layouts until it repeats. So speaker-assignment is not really random...
If you try Fraunhofer's mp3 surround player with the encoded 6channel_id.wav the layout stays the same. But it does not react in any way to what you set in the Audio/MIDI config tool... This may be due to VLC using AuHAL for an output (like it is supposed to be) while the Fraunhofer mp3 surround player probably uses the old static-windows-channelorder method VLC used before that ignores the Audio/MIDI Speaker layout (CoreAudio?)..
And if you keep in mind the 3 steps VLC cycles through and f.ex. switch LS/RS with L/R you'll notice that VLC actually reacts to the speaker layout set in Audio/MIDI config, thanks to AuHAL!

I also noticed that Left/Right front (aka Normal stereo) is much louder than the other channels, but I think this can be fixed using the volume sliders in Audi/MIDI config...

So we need to find the person that's responsible for the AC97 driver, especially the Realtek ALC850 and ask him nicely to provide 8(7.1)-channel output (which OS X can do, just check out the Pulldown in the "Assign channel" window in Audio/MIDI!). If that's too hard to do, another option would be to provide two channels of silence for the missing Left/Right side speakers..

A way to check that the default channel layout is correct (so that programs like the mp3 surround player that don't use AuHAL but a fixed channel order with Core Audio) still work would be to get some generic 5.1 (or 7.1 if that's even readily available!) USB-device, plug it in and check with the mp3-surround player. Don't worry, all the ones I tried worked, there's a generic USB class for such devices.. I recommend the Terratec Aureon 5.1 USB, all these 5.1-headphones make it kinda hard to tell where the sound is really coming from! ;-)

btw: The M-Audio Sonica Theater can do 7.1 on the Mac - but they have their own software for OS X. Still, i think they also work with Audio/MIDI if you set them to "passthrough" IIRC, but from what I remember they placed the two extra channels BEHIND the listener as some sort of "enhanced back center", not directly on the sides (like the Realtek and other PC-manufacturers aim to do)... This could be somewhat compensated for using the Speaker assignment in Audio/MIDI, just move LS/RS to L/R and the two "back centers" (can't remember what they were called) to LS/RS..

[kaid]

A little update:
If you check here, you'll see that the ALC850 is the only 8-channel Codec that Realtek ever made. In other words: Users of the ALC65x Codecs won't have the problem we are experiencing, since their MoBos only offer 6 channels!
Maybe if we could edit some plist so that the 850 is recognized as an 8-channel device instead of 6-channel? That should do the job already!.. I checked the info.plist in /System/Library/Extensions/AppleAC97Audio.kext/Contents/PlugIns/AppleAC97AudioIntelICH.kext/Contents, but there's no mention of the Codec's capabilities in there... I tried changing the ICHtype of the Nvidia entry from 99 to 8 (in Intels ICH6 entry that's the only place where I can see an Integer 6!), but it didn't seem to change anything (worked just like before!)...
Anyone know any other place where we could look? IOkit.framework looks promising, lots of hits on "channel" in IOAudioDefines.h and IOAudioTypes.h...