No...not if they're working in the Control Panel, and if the new Office
sounds work over your speakers. I've seen other people post this that it
might be related to the speech engine that comes with Office XP, so you
could try disabling that, if you're not going to use the speech input.
Also, you might try posting to a Windows newsgroup to see if anyone there
has any ideas... or you could try Kelly Theriot's page, which has some fixes
for sound problems.
Troubleshooting Windows XP, Tweaks and Fixes for Windows XP:
http://www.kellys-korner-xp.com/top10faqs.htm ("Where did my sounds go?")