ProSafe GS108 acts like a hub

I noticed a strange issue with my connectivity. Whenver I copy large files forom a PC connected to GS108, all other devices connected loose all bandwidth, even Netflix menu won't load. If I interrupt transfer everything goes back to normal.

It acts like a hub, dosen't share bandwidth at all between various ports...

I couldn't belive it was this heavy duty metal SOHO switch, but I just tried replacing it with cheap plastic Trednet Gigabit switch and issue is gone.

About my network. I have my main router/switch (Mirotik) connected to another Netgear gigabit switch in the basement from where one of the CAT5-e goes to GS108.

Is this switch just bad or am I missing something?