TV very very slow and speed change on FTTH link (>600Mbit/s)

Hello,

One of my customer has problem with TeamViewer.

Despite very high speed, TV can be very slow and unresponsible usually.

Sometimes it works great.

One try, we start two sessions on a customer computer. The mine works great, the other people was very unresponsible.


I would like to diagnose why, someone can help me ?


Thank you.