I am running Lubuntu 14.04 on my PowerBookG4 (PowerBook 3.5) and I am having this problem too.
I have already followed the advices in PowerPCFAQ (https://wiki.ubuntu.com/PowerPCFAQ#Why_do_I_have_no_sound.3F) to configure the /etc/modules and /etc/modprobe.d but it cannot solve the sound problem.
I am going to give up 14.04 and install 12.04 to have a try!!
I am running Lubuntu 14.04 on my PowerBookG4 (PowerBook 3.5) and I am having this problem too.
I have already followed the advices in PowerPCFAQ (https:/ /wiki.ubuntu. com/PowerPCFAQ# Why_do_ I_have_ no_sound. 3F) to configure the /etc/modules and /etc/modprobe.d but it cannot solve the sound problem.
I am going to give up 14.04 and install 12.04 to have a try!!