try this

[hildebrand_us <hildebrand_us@yahoo.com>]

Try this. Ensure that your wife's user is also subscribed to the audio group(It may not be and could be causing the problem). Debian by default makes the first user subscribed to audio(which is probably yours) and somehow this was not done for the new account(of your wife). This can be easily done in KUser to add the other account to the audio group. 
I had a similar problem for cd burning once where the user needed to be part of cdrom group in order to be able to do burning. So as an extension I feel this may be the problem.