VPN - Remote access RDP video streaming performance issue

Question

Hello fellas, 
 
 My goal here is either to confirm / understand what is happening. 
 
 Situation 
 One client using a VPN to remote in our work network. From there, he opens an RDP connection to a server where he needs to stream video. The video is captured at 60-80Hz but shown at 4-5Hz. 
 
 When the client is on-site and using his RDP to stream video, everything is running as expected. 
 We have tried using three different internet speed to see if it was the issue. 
 We tested it on MacOS and Windows 10. 
 Everything is running smoothly except video streaming.

Questions 
 
 Is it related to VPN compression or encryption? 
 Could it be related to a setting in the config file?

He is the only one having a session open during our test. 
 
 Cheers, Steven

Nevets24 · Accepted Answer

Hello, 
 
 I forgot to update this tread. 
 
 Thanks for the hint. After more testing, it point heavily on some settings within the application. Inside the network, everything is fine, however at the moment you come from another address - VPN, NAT rule allowing us to remote directly - we have a major streaming performance issue. We do not support / provide the application our client is using, therefore playing with the settings isn't an option. 
 That being said, the Sophos device isn't the issue. 
 
 Steven