Line out and internal speaker issues when using Linux - IBM IntelliStation Z Pro

Resolving The Problem

Source
RETAIN tip: H182529

Symptom  
The internal speaker will still function even though the front or rear line-out port is connected. Both the rear line-out and the front line-out channels are always enabled.
 
Affected configurations
The system may be an IntelliStation Z Pro, type 6223, any model.
 
The following NOSs are affected:  

• Red Hat Enterprise Linux, version 3.
• SUSE Linux Desktop 1.0.

Note: This does not imply that the network operating system will work under all combinations of hardware and software. Please see the compatibility page for more information:

http://www.ibm.com/servers/eserver/serverproven/compat/us/

Solution  
There is no current fix for this issue; it is a current limitation of the above operating systems. We are working with Red Hat and SUSE to get these issues resolved in future versions of these products.
 
Workaround  
Red Hat:  
The internal speaker can be controlled by selecting Sound and Video, then selecting Volume Control, from the GNOME menu or typing gnome-volume-control from an X terminal. From this tool you can adjust the internal speaker's volume by adjusting the phout audio channel.
 
Alternately, to disable the internal speaker you can disconnect the internal speaker from the system board. Refer to your hardware manual for the location of this device.
 
SUSE:  
The internal speaker can be controlled by starting YaST, (as root type yast2 at a command prompt) and selecting Hardware, then selecting Sound, then selecting Volume.   From here you can control the internal speaker's volume by adjusting the Master Mono volume level.  To disable the internal speaker, you can disconnect the internal speaker from the system board. Refer to your hardware manual for the location of this device.
 
Additional information
Red Hat:  
RHEL3 uses the OSS subsystem to control audio. The driver in RHEL3 applies the AC'97 specification up to version 2.2. AC'97 version 2.3 is required in the driver to implement this feature. Future Red Hat products will have newer versions of the OSS audio subsystem.
 
SUSE:  
SUSE Linux Desktop 1.0 uses the ALSA subsystem to control audio. SLD 1.0 has a downlevel ALSA subsystem which causes this problem. You are unable to control individual audio channels using the current software. Future SUSE products will have newer versions of the ALSA audio subsystem.