No sound, can't upgrade to 18.10

I'm also getting the connection to PulseAudio failed error and I've tried editing the default.pa file but those don't work. I've tried upgrading to 18.10 but when I click on the upgrade button nothing happens. I'm a complete Linux n00b so I have no idea what I'm doing.

If you are using the 18.10 image from Digital Loggers, you need to use dd to copy it to the integrated eMMC drive at /dev/mmcblk0. From their docs:

"These images are not installers.
Boot from a USB or uSD card and use dd to copy the image. Use BIOS settings to change the boot order.
Example: # dd if=/where/you/put/the/image.img of=/dev/mmcblk0 bs=1024k oflag=dsync status=progress

These images have a user 'atomicpi' with an assigned password 'atomicpi'."