I have a call transfer issue with a Quadro M8L on version 5.2.40 with Snom 300 (some on 8.4.3 and some on 8.7.19) and a Snom 870 on 8.7.19. Have 6 FXO incoming lines.

The transfer problem is that when a call transfer is attempted from one extension to another, when the extension receiving the transfer is picked up, the call disconnects immediately. I have tested this with both internal and external calls.

Some phones were updated to newer firmware as a test for resolving issue.
SRTP is always accept unsecure calls.

System has been up and running no problem for 3 years. The problem did not exist until my client had a MSP come in and attempt to perform a network security and inventory scan with a product called iScan. For some reason after a few minutes of them scanning the network devices it locked up the Epigy M8L and none of the phones could receive or dial an outside line. Rebooted the Epigy and had to do a Reset on the phones themselves to get the system back up and running but I have this one issue remaining.