Weird Net Traffic Issue

[Sora21]

Hi all
Something very weird came up today,and i cant figure anything out, so i need ur help please.
I was watching a video at YT and noticed major network traffic(i have a network meter gadget)
So much downloading as if i was having torrent open
anyways i closed up everything but the downloading still kept going
task manager's recource monitor says nothing is downloading
i even had netbalancer check the processes and showed the same.as if theres nothing downloading
(note: the gadget is not bugged or sth. its true something is downloading cuz the internet becomes really slow)

i tried reboot, everything ok untill i get to yt again and play a video.then it starts again.

reboot again.i tried watching via chrome. didnt happen. no traffic no nothing
back to firefox and it starts again.
i tried uninstalling flash player but it did nothing

its no windows updating, no antivirus updating or any other software. all closed up.
so i thought it could be some malware
tried bitdefender full scan both in and out of windows (boot full scan) . all clear


so basically i have big downstream when i start playing a video at YT which goes on full bandwidth even if firefox and all processes are closed. thanks in advance for your help

(p.s. i5 950 , Asus P6DT Deluxe,Asus 5870 HDRadeon,, Win7 64-Bit)

 

[Apachez]

tcpdump is your friend...

Either run it through a span-port of your switch or run it directly on the affected host.

Something like: tcpdump -s0 -w file.pcap

and then press ctrl+c to stop it.

 

[Sora21]

im sorry i have no idea what you advised me to do and i wasnt able to find information on the net
this is a linux command?
how do i run it " through a span-port of your switch or run it directly on the affected host."
it doesnt seem pretty obvious to me :/