No Surround Sound and only 1/2 Volume

I’ve recently installed Kodi 17 on a W8.1 desktop run to AV amp. Only the front speakers work although the others work fine through Xbox and speaker test on same amp. The volume is also less than 50% of normal. I was referred to the Wiki Log File/Easy but the instructions there don’t work in that in Step 1 shows Programs>Get More>Kodi Logfile Uploader but there is no Get More option to proceed to the next steps. YT vids are incomplete or outdated, etc. so that is no help either. Can someone please help me out here?