[Asterisk-Users] Asterisk Native Sound Distortion (ulaw)

Kristian Kielhofner kris at krisk.org
Mon Sep 11 08:51:03 MST 2006

Tzafrir Cohen wrote:
> On Sat, Jul 01, 2006 at 01:29:30PM +0200, Paul Hewlett wrote:
>>   Maybe on other distros the sound files are being read from an IDe disk and 
>>the interrupts generated are distorting the sound - on astlinux the 
>>soundfiles are in a memory filesystem - no interrupts - no distortion ?
> Bigger systems have large buffers.
> An hourly cron job to can the sound files you normally use to /dev/null?

	Although tmpfs is used extensively in AstLinux, all of the sound 
prompts are stored and read from disk.  This issue has come up several 
times, and I have no idea why they sound so much better in AstLinux. 
Don't get me wrong - I'm glad they do, but they should work equally well 
for all users of Asterisk, not just those that use AstLinux!

	Actually, now that I think about it, AstLinux does have one crucial 
difference.  By default, DMA for IDE transfers are disabled (better 
compatibility with compact flash - rather safe than sorry)...  I should 
try to enable DMA on a system that supports it and see what happens.

Kristian Kielhofner

More information about the asterisk-users mailing list