[2k10]

Hi! 
I have buffering issues watching 4k movies though my nas.
 
My setup is the following. Router goes with cat6 to a switch. From the switch cat6 goes to nas Synology ds414j, and then a cat6 from switch to my laptop.
I launch kodi from my laptop and use it as the media center.

I tried setting up the advancedsettings.xml but noticed no difference.
Then i tried the ares wizard and it created the following settings for me. 

<advancedsettings>
    <cache>
        <buffermode>2</buffermode>
        <memorysize>524288000</memorysize>
        <readfactor>5</readfactor>
        <curlclienttimeout>10</curlclienttimeout>
        <curllowspeedtime>10</curllowspeedtime>
    </cache>
</advancedsettings>.

Playing 4k stutters alot.
Playing 1080 also buffers some just when starting up but plays smoothly afterwards.

Im not too experienced with kodi but after spending the weekend trying to get it to work with different settings i don't know what the issue is.
Any clues?

My internet is 100 Mbit/s download and 10 Mbit/s upload.
Do i have to upgrade?
If so would it be enough to upgrade to 100/100?