I am using ktorrent 2.0.3, with a 1,500/256 connection.
The problem; I have uploads set to 16kbs which works fine at night (gmt +10) but from around 11am my upload speed drops to 8kbs and stays there. Download speed is not affected My ISP off peak period is from 12am to 12pm.
I have contacted my ISP and they say they don't shape uploads or do port blocking.
Could someone help explain why this might be happening and what if anything I can do about it.

Maybe your ISP can't keep their advertised upload speed during peak hours?

Have you checked to see if another upload also goes at the reduced speed, to make sure it's not ktorrent-specific (I highly doubt it's a ktorrent bug or anything like that...)

Thanks for your reply jdong, Turned out it was my stuff-up. I had been playing with the Bandwidth Scheduler and forgot to set things back to normal.

I'm not really stupid, I just do stupid things sometimes......