Downloading Question, Help!

[lavenderAC]

Sorry to ask again, but I find this really weird and don't know how to fix

I am a cable user, and my download speed has always been good except in the last month or so. But the thing is its working fine with certain software but not the others.

Softwares that have good dl speed are: flashget and other IE/firefox default dl (50kb+/s)

Softwares that have problem: overnet, bitcomet, azerues, abc, etc

I use linksys wireless router, and I have opened my port from 6000-7000. I also changed all the ports in these p2p software in this range and it has always been working fine except recently its not.
Most of time it will go up to 10-20kb/s then back down again in a few secs.
Does it make a different that I just open ports from certain range? Or should I open it one by one, say bitcomet 6880, abc 6223, etc?

Could it be virus or firewall thats causing this? If so, how can I check and clear them?

Thanks

 

[Osiris]

it all depends on what there connection is too.

 

[lavenderAC]

For bittorrent, i am downloading at very very slow speed with everything, even with the ones that have lots of seeds

For overnet, I have lots of connections as well, but it simply doesn't download or download at really slow speed

 

[TheMajor]

I would try forwarding the ports seperately.