Make up your mind , is it a hardware problem or not?
Originally Posted by suxxor
If you still want to continue troublshooting, open System_Preferences_Sound and check the settings there. First, turn everything to Autodetect. Try playing sound/media. Next change everything to ALSA. Try playing sound/media. Next change everything to "PulseAudio Sound Server" (If you have that setting). Try playing sound/media.
If none of the above work, or if you cannot find any of the settings above, post a screenshot of the above window, and also open a terminal (Applications-Accessories-Terminal) and post the output of the below commands
lspci -v | grep -i -E sound\|multim\|audio
lsmod | grep -i snd