remote extensions combined with soft phone and assistant

[zman574]

I have a remote location that I want to make a mixed environment. I have 6 Cisco SPA504G phones and I want to use the softphone with 2 of the computer at the same location. I know that my setup may sound a bit messy but this is how I have the cisco phones set up (it is the only way they will all work)

SPA 1 sip port 5061
SPA 2 sip port 5062
SPA 3 sip port 5063
Etc,etc

Then in the remote router I have port forwarding set up to forward each of the ports to the respective static ip of the phone.

For more than a week that work flawlessly, with no outages and not problems. Then 2 days ago I installed the 3cx assistant and 1 softphone in the office to see how it would react. It was not an instant issue but eventually they started to have dropped calls, and hard phones that would not register. I went and removed the softphones and assistants from the computers and they are back up with no issues.

Unfortantly I have not tested the softphone and the assistant by themselves to see which one is causing the issue but that will be my next step.

The softphone was using the tunnel and the basic settings. Do you have any suggestions on how to handle this. Should I work with advanced settings and port forward to a different sip port and forward to the ip address of the computer?