Recording an annoucement not working

Hi Folks,
I’m currently trying to get my first freepbx system going and have trouble with recording an announcement from a phone.

using the system recording module I enter my extension number, dial *77 and speak. *99 enables me to hear my recording ok.

However when I come to name and save the recording I get an error message:

unable to add /var/lib/asterisk/sounds/custom/blah.wav - Can not read file!

Any ideas what’s wrong with my setup? It’s on debian etch with freepbx V2.2.1 and asterisk 1.2.17

many thanks,
Robin.