Softphone + HT502 Issue

I have an HT502 which works great, but as soon as I connect with my softphone all incoming calls only ring the softphone. The HT502 will not ring. I’m OK with this except for when I disconnect the softphone incoming calls will immediately drop. It will not even go to the failover or VM. Incoming calls will not work until the HT502 reregisters. Rebooting it always works.
I’ve tried the softphone outside my home network, and it still causes the same problem, so I don’t think it’s NAT related.

Can anyone suggest any troubleshooting tips that may help me figure this out?

I guess the first obvious question: Is it possible to use a soft phone at the same time as the HT 502 is online? This usually works without issue if I configure the softphone to not register for incoming calls, but of course I can’t answer calls on the soft phone.

Thank You

I have found the opposite issue. I have the ht702 and only it will ring inbound (not the softphone). sipdroid (softphone) appears to be registered as it is able to make outbound calls. if i turn off the ht i get the unavailable message.

This is not much help to the op but using 3cx i get inbound and outbound calls working.