I'm fresh to ubuntu, i installed some softwares like photoshop and kodi. Now before installing kodi, i could hear things right(I have a HP laptop, built-in speakers)(btw i installed kodi by comands if this makes a difference). I restarted the laptop and when it opened, i could not hear any sound. I went on youtube, clicked a random video... no sound. But, when i plug my headphones, i can hear sound. Is this a software problem or hardware?