RT30 Contacts slow to load

[Nigel 21]

I'm setting up a new phone system with 8 handsets W56H and W60B base station
I have also used a RT30 repeater to extend the range
when the phones are connected to the repeater the contacts on the phone load very slowly?
I've tried moving the repeater nearer so the dect led is green but it make no difference.
All help and advice greatly appreciated