Troubleshoot Linux Operating System KNOPPIX 7.2 64bit (knoppix64) with Windows XP 32bit as the Guest OS. Windows XP 32 bit Guest OS no sound and no audio when playing YouTube

I was caught off guarded this time and I manage to find out that the Alsamixer  ' Front '  volume was at the lowest volume. This can be seen as shown below.

So, what I did is to just increase the ' Front ' volume on the Alsamixer GUI to maximum and everything is back to normal as shown below.