I tried messing with it again this morning.. still no joy.
Here's my system info:
DSM Ver: DSM 6.1.7-15284 Update 3
DSM image: DS3615xs
Installation type: Bare metal
Hardware: HP Pro 3500 Series MT
Video Station version: 2.4.1-1554 (I was running the latest version but decided to downgrade)
Some additional info:
I get the "Music or videos don't play or display properly because the given codec is not successfully activated. Please check your Internet connection." error after disabling internet access and then trying to play a video. Output of cat /usr/syno/etc/codec/activation.conf remains as below -even after trying to play videos:
{"success":true,"activated_codec":["hevc_dec","ac3_dec","h264_dec","h264_enc","aac_dec","aac_enc","mpeg4part2_dec","vc1_dec","vc1_enc"],"token":"123456789987654abc"}
But goes to the output below after enabling internet access:
{"success":false,"msg":"SN format is wrong."}
ffmpeg package is installed (version 4.2.1-23) from SynoCommunity