Configure escape key

We have a hub/spoke type of DIGI setup.
Home office has (Digi Home) and remote sites are DIGI’s 2,3,4,etc.
We are looking to SSH to DIGI Home and then modem to DIGI’s 2,3,4,etc. We are able to SSH to DIGI Home and modem to the remote DIGI units but are having issues with changing to a different port on the remote DIGI’s. When we use the Ctrl^[ the modem connection is broken instead of the remote DIGI ports.
How can we modify the escape keys? We’d probably modify the escape keys on the Home unit and keep the remote units the default of Ctrl^[.