I've added two OKTO/HECS probe pods to my stack, one with a Communitron HG-55 antenna, the other a DTS-M1 antenna, both with battery power and solar panels, but when I separate them in orbit around Duna, only one of them will connect to the network (in a test launch, around Kerbin, they both connect, suggesting that the DTS-M1, which doesn't have the range of the HG-55, is not able to relay through the HG-55).
See below pics.
What am I missing?
The stack in the VAB:
"Dead" probe (at top of stack):
Connected probe: