static when adding opening sound

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Leland
Developer
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Re: static when adding opening sound

Post by Leland » Sun Dec 21, 2014 12:28 am

Incidentally, I wasn't getting the crackle at first. I then went into AMS and changed the output device to 48000, 24-bit integer. Then it started to happen. But, it only happens on the first play. Any subsequent play works fine.

Off the top of my head, it might be some left over cruft from the device scanning that is done at startup and that playing/stopping the device clears it.

Gonna be "fun" to track down.

Leland
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Re: static when adding opening sound

Post by Leland » Sun Dec 21, 2014 12:33 am

Leland wrote:I get the same crackle on my new mini, so now I just gotta get a build environment set on on Yosemite...did it once...reinstalled Yosemite...didn't bother to set up the build env again. :-(
Nope, that's not it. Closing the project (while staying in Audacity) and opening it again produces the same crackle.

I'll withhold further guess until I actually know what the heck I'm talking about. :-)

Leland
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Re: static when adding opening sound

Post by Leland » Sun Dec 21, 2014 2:13 am

I'm pretty sure it's caused by a mismatch in sample rates between what the hardware is wanting and what Audacity is sending to it.

Using one of the crackle.aup project above, I'm able to make the problem stop by ensuring that the sample rate on Audacity's Quality Preferences tab is the same as what I have set in AMS for my output device.

Any difference and the problem occurs.

Again, it's only for the first Play. All subsequent ones are okay.

And (this really sucks) I can't get it to happen in Debug builds, just Release builds.

So, anyway, back to it...

Leland
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Re: static when adding opening sound

Post by Leland » Sun Dec 21, 2014 4:00 am

I've located the cause and have a solution, but want to discuss it with the other developers before committing.

Leland

jchaps82
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Re: static when adding opening sound

Post by jchaps82 » Fri Jan 02, 2015 4:08 pm

Thank you guys for all the input. Is there a way to fix this for the next program update?

Cheers,
Jesse

Leland
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Re: static when adding opening sound

Post by Leland » Fri Jan 02, 2015 5:07 pm

jchaps82 wrote:Thank you guys for all the input. Is there a way to fix this for the next program update?

Cheers,
Jesse
I applied the fix on Dec 22, so if you;'d like to try it, grab the latest "nightly" from:

http://audacity.homerow.net/index.php?d ... order=desc

Leland

jchaps82
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Re: static when adding opening sound

Post by jchaps82 » Fri Jan 02, 2015 5:16 pm

Thanks!!

Gale Andrews
Quality Assurance
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Re: static when adding opening sound

Post by Gale Andrews » Fri Jan 02, 2015 10:37 pm

jchaps82 wrote:Thanks!!
Does that mean it works for you, or are you yet to try? ;)

Gale
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