Thanks Miles for your complete answer. 


>     Dmesg message in Mobilepro 780:  audio0 at vraudio0:half duplex
>
> No.
>
> Audio does not work for me, but IIRC playing an auddio file results in
> a delay the same length as the file.  Maybe the kernel does not
> correctly power on the analog components when one opens the audio
> driver.  An interesting test would be to boot NetBSD while WinCE is
> playing a sound.

In the Web page of Netbsd/hpcmips is an audio Link "* to driver for VR4121 
(NetBSD-current, 2002 Jan.6 to later) by Katsuomi Hamajima", the Link this 
broken one (was a file to aiu.tar with two "* diff*). IIs it possible to 
correctly install the sound in Mobilepro 780?