As the title says the preffered master box is checked as is the sync to external box. All the routing boxes are green ticks. I’m new to Dante and I’m struggling
Maybe you should try struggeling with the DANTE Controller
What is the Dante Controller showing?
We need more information
it’s showing a red cross on the network status tab for the console, I’m pretty sure it’s a sample rate thing as the tool tips on the routing page say’s’incorrect channel format source and destination channels don’t match’. It was working last night but now the system is in Aviemore and I’m in Glasgow. It’s all new to both of us the desk is fine and the PA is working it’s the link from the Dante 64 cart to DVS that’s causing grief.
We did a dry run yesterday and thought we’d saved everything but alas it would appear not 
Wich Dante Card?
M-Dante, Dante 64/128
Wich sample Rate?
Wich devices are involved?
Found the issue Reaper doesn’t always play nice and actually work at the sample rate it shows on the main mixing page ( I think that is just the info the driver is reporting), my colleague isn’t a great user of DAW’s so didn’t realise this, everything was at 96k but on the audio device page in reaper at the request sample rate box it was still set at 48k. Why do these things always happen when your in a hurry and miles from anyone who knows what to do Lesson learned thankfully nothing critical and the much maligned USB recorder ran for 2hours with no problem.