We have a strange situation.

One of our applications written in vb.net has it's data etc hosted in Azure.  When running the application from the office over a site to site vpn to the Azure endpoint everything works perfectly well eg a typical report runs in about 5 seconds.  However, when the users connect over the Azure software vpn on their home machines (all users regardless of local internet performance) the whole application slows down dramatically eg 90 seconds plus for the same report.  The IT Infrastructure team have exhausted their investigations and can find not reason why.

Running commands at TCL using a Telnet application all seems OK but when running the app (uses port 31438 for RPC) is when the speed issue is experienced.

Has anyone seen this or have any suggestions on where we might need to look?