X86 Hardware issues (Graphics, WiFi, Onboard Sound, external DACs, Disks, BIOS/UEFI Boot problems etc.)

Hello My hardware,

Brand:MSI
Model: MSI MS-163C (VR601) Laptop(Pentium Dualcore)
Booting From: HDD
Sound Card: Creative x-fi usb 5.1(Optical out → DAC) and My DAC’s USB input (PCM2704)
Volumio 2.916

I’m using Volumio 2.916, running verry well. Specially Creative x-fi USB’s sound is good.

I tried Volumio 3.179. When I’im using My Dac’s USB input sound is same with 2.916. but When using Creative x-fi usb 5.1, the sound is worse than before.

Another Question,

I keep my media files on my computer’s hard drive(INTERNAL). Can I install the new version without deleting these files? (Booting from HDD)

Thanx,
Best Regards
Rüstem