Re: kern/51784: "Synthesized" speaker hums

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/51784; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: Nathanial Sloss <nat%netbsd.org@localhost>
Cc: gnats-bugs%netbsd.org@localhost
Subject: Re: kern/51784: "Synthesized" speaker hums
Date: Thu, 25 May 2017 17:18:41 +0800 (+08)

 > I've since found there is quality loss converting from ulaw to signed linear.
 >
 > I now have a 16 bit 1 channel signed linear bell.
 >
 > To use apply this patch:
 > ftp.netbsd.org/pub/NetBSD/misc/nat/hiresbell-linear.diff
 > and add the following to your kernel config:
 > options HIRES_BELL
 >
 > Please let me know if this resolves the "hum" this time?
 
 Unfortunately the hum persists.
 
 Interestingly, there is no hum when doing "normal" audio/video playback 
 (such as running mplayer, or visiting a video clip in firefox!).  It is 
 only a problem when executing a command similar to
 
  	# echo  T60L1CP1CP1C > /dev/speaker
 
 
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