Getting sound working

[JanKok]

I'm trying to get HDMI sound working using the ubuntu-lxde-14.03.06-p16g1.img.

1. I can watch videos in Firefox but there is no sound. How can I make sound work?

2. It would be nice if the music players just worked "out of the box". As it is now with the current image they need some configuration to work:

LXMusic: File->Preferences->Audio tab->Plugin
choose "Advanced Linux Sound Architecture", click OK.

SMPlayer: Options->Preferences (or just click the screwdriver icon)->General->Audio tab-Output Driver
choose alsa, click OK.

3. I used adduser to create a new user account and group for myself instead of using the linaro account. When I'm logged into the new account, audio doesnt work unless I add the new user name to the audio group in /etc/group. I'm wondering if this is the best way to control permissions? Is there some way to allow all users to use audio without having to edit /etc/group? (The same question goes for other permissions. For example, sudo is enabled by adding the user name to the admin group.)

4. LXMusic and SMPlayer play the "silence" sample music track at different pitches! LXMusic plays it in the key of A, SMPlayer plays it in Bb+. They can't both be right! What does it take to get them to play music at the right pitch?

[shodruk]

Try these configurations: http://elinux.org/Parallella_Speed_Up_Ubuntu

[JanKok]

After going through that procedure, the two music players play at the same pitch. (Thanks!) However, there is still no sound from Firefox when playing youtube videos. Do I need to set the driver for Firefox, as I had to for the music players? Or does audio not work when the screen resolution is 1920x1080?

[JanKok]

So how do I get sound from Firefox?