asterisk users - Mar 2007 - asterisk 1.4: choppy voicemail sound after upgrade from 1.2.9.1

Hi,
after upgrading my server (Debian 3.1 + tdm400p + monoBRI) from 
Asterisk1.2.9.1 to new Asterisk 1.4 (same hw, same os) I got the 
voicemail sounds randomly chopped. I checked the sounds with  a player 
and they seem good. I made tests with default modules.conf settings 
(noload => chan_alsa.so and ;noload => chan_oss.so) and also trying to 
change them, without success. Is there anybody who knows if there are 
new conf files/parameters inside Asterisk 1.4 controlling sounds 
reproduction and where are located?

TIA


Giorgio Incantalupo