Hi shivalaxmi,
I see that you are having a couple of issues with your notebook. Are you getting any error messages when you try to install the BIOS update and UEFI downloads? Does the sound issue happen with other programs? Is the movie a DVD or a video streaming online? What operating system are you running? As there are several notebooks in the G6 series can I get your product number please? With information I should be able to find you a sound driver to fix the sound issue.
Thank you,