Hi,
Thanks for posting in Q&A platform.
Based on provided information, it seems that the issue is when Load balancer was enabled, the network speed of interface 192.168.1.2 was slow, and when the load balancer was disabled, the network speed of interface 192.168.1.2 was became normal. How about the network speed of other devices when the load balancer enabled and disabled?
Since the network speed is affected by multiple factors, for this speed slow issue, we need to analyze performance and network traffic log to find any clues. Unfortunately, analysis of performance and network log is beyond our forum support level and due to forum security policy, we have no such channel to collect user log information. So, if you want to find the cause, we recommend you open a case with MS Professional tech support service, they will help you open a phone or email case to Microsoft, so that you would get a technical support on a one-to-one basis while ensuring confidential information.
Here is the link:
https://support.microsoft.com/en-us/gp/customer-service-phone-numbers
Best Regards,
Sunny
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