How to properly configure the D-LINK DGS-1008A/D1A switch?

Question

network hardware

Internet distribution is configured according to this scheme

. Computers that work after the switch have worse Internet than those that work directly from the router.
Help to configure the router in this scheme.
Switch Model: D-LINK Switch DGS-1008A/D1A

Answer 1

DGS-1008a is an unmanaged switch, it has no settings. If something does not work or does not work correctly, this is a problem in the cables or in the hardware.

Answer 2

Explain the concept of "much worse."
The switch should not make any changes to the traffic. Reset it to default and enable it without configuration. If the problem persists, check the patchcords. If the cables are OK, throw the switch into a landfill