I recently upgraded to Immunet 5 from Immunet 3, and I'm noticing higher CPU usage with Sourcefire Connector program (regularly 10-30%, which is too much for me).
I'm running Windows 10, English, 64-bit, version 1607, OS Build 14393.321
Not sure if the following is related, but the high CPU usage happened simultaneously with a Windows update that revived Windows Defender, which is now taking up even more CPU capacity than Immunet, when Defender automatically turns its "continuous" mode back on (which I always promptly turn off).
I also use IDrive online backup and a local Seagate hardrive with scheduled daily backup.
Maybe I have the wrong settings activated for Immunet?