Write operation is happening from 1 Gigabit port instead of 10 Gigabit port in NetGear switch and its random

Write operation is happening from 1 Gigabit port instead of 10 Gigabit
port in NetGear switch and its random

We have a Synology system which is connected with NetGear switch. We
passed 2, 10 gigabit cables from synology to switch. We connected HP
server with switch with 2, 10 gigabit port. We connected one more network
on 1 gigabit port to a switch. We installed VMWare on the server and
testing write test on Synology system. While testing, some time write
operation is going through 1 gigabit port. The NetGear switch is smart
enough to route the traffic to the fastest connection (i.e. from 10
gigabit port). This thing is happening on random. Sometimes write
operation is going through 1 gigabit port and sometime its going through
10 gigabit port. We are performing write test from the server which is
connected with two 10 gigabit port.