Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 30 Jul 2014 21:27:38 -0400 (EDT)
From:      Benjamin Kaduk <kaduk@MIT.EDU>
To:        Dutch Ingraham <stoa@gmx.us>
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: Audio CDs Not Playing
Message-ID:  <alpine.GSO.1.10.1407302123080.21571@multics.mit.edu>
In-Reply-To: <53D97A50.8090006@gmx.us>
References:  <53D97A50.8090006@gmx.us>

next in thread | previous in thread | raw e-mail | index | archive | help
I am not sure how helpful this will be, but

On Wed, 30 Jul 2014, Dutch Ingraham wrote:

> Greetings:
>
> I asked this question on freebsd-questions a couple of days ago and have 
> received zero responses, so I'm posting here and asking the hackers for their 
> help.  Here's the problem:
>
> I'm having trouble with playing audio CDs; specifically, they won't
> play at all.  Secondarily, it appears as though if they would play, I
> would need to be root to do so.
>
> I am issuing the <cdcontrol -f /dev/cd0 play 1> command and the CD

I believe that for this command to actually produce audio playback 
requires a hardwired connection between the optical drive and the sound 
card (or motherboard, if it's an integrated sound card as is the norm 
these days); this is a dedicated 4-pin cable (or so; it's been a while) 
that's distinct from the power and (P|S)ATA data cable for the drive. 
That said, I would mostly expect this cdcontrol command to still spin the 
drive up even if that connection is not in place...

> simply will not play (it does not physically spin).  However, if I issue
> <cdcontrol /dev/cd0 eject>, the CD will eject; if I issue
> <cdcontrol /dev/cd0 info>, I will receive the tracks information, etc.
> So it appears as though communication is happening, but the CD will not
> play.  If I issue these commands as a regular user, I receive a
> "permission denied" message; if run as root, simply nothing happens -
> no error, nothing.  In fact, issuing <echo $?> returns 0.
>
> PS - This issue is not limited to CLI commands; VLC will issue the
> error "VLC is unable to open the MRL 'cdda:///dev/cd0'. Check the
> log for details." There is no log info that I can find.  In addition, I
> can burn a cd with xfburn, but only as root.  My fstab has the standard entry 
> for CDs.  Sound does work, as I can generate white noise.

It does not seem very surprising to me that root privilege is required to 
(e.g.) burn a CD.  This is related to at least the permissions on on the 
/dev/cd0 device node, which I don't think were in the context I trimmed...

-Ben



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.GSO.1.10.1407302123080.21571>