I have the P4515 shared from a Windows 2012 version using the latest PCL5 64bit drivers (I've also tried the latest PCL6 drivers). I've applied the latest firmware, the printer port is set to the IP address, and I've tried changing the setting to print directly to the printer. It's all on an internal, gigabit network.
Each time a user prints several jobs at once, they are spooled properly on the server but there is a 5-10 second delay between each job as it's printed. What could be causing this?