You need to fix the ethernet issue..
But it sounds wrong.
The Flying Fish wrote:
I have my MacBook connected to the time capsules with USB and Thunderbolt but whatever I do they only connect wirelessly.
How are the two Time Capsules connected?
Why are you using two different connections? You are going to run into IP issues here.. you cannot do it like that.
The two TC should be linked to each other.. they are still network devices.. one at least should be bridged to the other. Using your fastest ethernet connection you can plug into either of the TC.. then get access to both over the network. If you lose access when you turn off wireless then you haven't got it setup correctly.. start over again.
One TC as router.. one TC as bridge.. or if you have a main router, both in bridge.. linked to each other.
ensure the ethernet is getting IP correctly and airport utility is showing both TC.