Keyboard and touchpad not working

Hello,

A little over a year ago I bought a Dell Inspiron 11 3000 only to find the keyboard and touchpad would randomly stop working and randomly switch back on again. At first I thought it was just a small glitch in the system and since it didn't happen too often it hadn't really bothered me. Through the months, however, the issue started to get worse to the point where even after I'd restart it still wouldn't work. Now it's only by luck I'd be able to catch the physical keyboard and touchpad working which quite frustrates and inconveniences me. I have also noticed, and I don't know if it's actually related, my laptop's speakers have also gradually developed a loud fuzzy noise whenever I play something on the internal speakers. 

This has reached a really frustrating point and I would have tried reformatting or updating to Windows 10 to see if it would help but  I have a large number of files and apps which can't all be backed up. I want to fix this problem but I don't want to lose any of my data. What is the issue here and how can I solve it?