Recently I upgraded from ubuntu 9.04 (Jaunty Jackalope) to ubuntu 9.10 (Karmic Koala). From the moment it booted it gave this annoying ticking sound through the speakers and also through the headphone every 10 -15 seconds. Grrr...
Extensive googling lead me to the solution. here it goes,
* Open /etc/modprobe.d/alsa-base.conf
* Goto the last line and comment out
options snd-hda-intel power_save=10 power_save_controller=N
* Now restart or reload the module and this annoying sound problem would stop for good.
Courtesy: I thank the ubuntu forum members for posting the solution. The reason behind this bug and detailed discussion could be found in the following links