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Operating System Specific Discussions => MorphOS => MorphOS -- Application questions and support => Topic started by: dougal on October 23, 2010, 04:10:40 PM

Title: Sound in MorphOS problem
Post by: dougal on October 23, 2010, 04:10:40 PM
Sometimes sound works, and sometimes it does not.

My system is a Power Mac G4.

I know that you are supposed to use a SB Live! and NOT the on-board sound of the Mac, but then how come sometimes sound works? Even on Youtube i get sound, but sometimes.

Is there some sort of hack or unofficial driver? as i dont have a SB Live! and id much rather use the Mac's built in sound card anyway.
Title: Re: Sound in MorphOS problem
Post by: Iggy on October 23, 2010, 05:08:37 PM
That is unusual. I too have a Powermac running MOS 2.6. Initially I only used the built in sound because I couldn't get the SB Live to work correctly. Then one of the MOS developers (FaB) pointed out that there are five selections that need to be set in the audio preferences section. The first is the music unit (that is displayed when you bring up audio preferences). The other AHI units (0-3) can be set when you click on the icon to the right of the Music Unit line.
All outputs must be set to your desired output device, but in your case I would assume MOS would default to all five being Apple output.

Look, I know it would involve a minor expense, but an SB live isa better solution. The built in sound is just horrible. You can find a SB live card on Ebay for about $5. If you can't find one, I'll sell you one. You won't regret the minor investment. The sound quality is much better.

Oh and BTW, what do you think of 2.6? I getting a big kick out of it. Its lightsyears faster than OSX and boots rediculously quickly.

Good luck with your problem.
Title: Re: Sound in MorphOS problem
Post by: Fab on October 23, 2010, 05:08:50 PM
Quote from: dougal;586427
Sometimes sound works, and sometimes it does not.

My system is a Power Mac G4.

I know that you are supposed to use a SB Live! and NOT the on-board sound of the Mac, but then how come sometimes sound works? Even on Youtube i get sound, but sometimes.

Is there some sort of hack or unofficial driver? as i dont have a SB Live! and id much rather use the Mac's built in sound card anyway.

Ok, there's many different topics involved here, actually. :)

Onboard sound works only for later powermac g4 models (3,4 to 3,6 IIRC). That said, in some cases (there are several slightly different powermac configs), the chip config is a bit particular and as a consequence, the gain is too low. This should be addressed in a next version. If you're in that too low volume case, you might want to use a SBLive. If you do, make sure you set SBLive mode for all ahi units, and not only for music unit: go to system preferences -> audio, and in the list at the top, go through each type (music unit, unit 0..3), and select the sblive HiFi 16bits stereo++ mode for each.

Now, about youtube, there's a bit more to know about AHI: OWB uses the AHI music unit, which is unfortunately exclusive (meaning if audio is allocated for it, not other application can access audio). This mode was used for latency reasons, but the problem is webkit will sometimes "leak" a media player instance (including audio task) until it thinks it doesn't need it anymore (in all cases, it will be disposed at program exit), which means audio might not be accessible anymore. Fortunately, there's a solution to make that exclusive mode non exclusive. :)
In system prefs -> audio, you would choose for music unit: "Unit0: mode". That way, it will redirect music unit requests to the shared ahi units.

Oh, and while i think about it... I hope you're not using Flash to play youtube content, but HTML5 (with the help of supplied userscripts). See OWB.readme in youtube section, in case you wouldn't.