UPNP load average high

[sgobi]

I have noticed with the Asus RT-N16 with build 13450 that whenever upnp is enabled the load average is always around 1.00. I have noticed that i always experience intermittent freezing in internet access. Whenever I am downloading there would be a temporary freezing like every 10 seconds or so. Also when I access websites it takes a long time showing connecting in the status bar of internet explorer. This was becoming a pain and that is when I checked my cpu utilization and found it to be around 97.3% idle. This is good because barely any cpu is being utilized. The upnp daemon is using 0.0% and no other process is using more than 0.3% of the cpu. This doesn't explain why the load average is more than 1.00. I then disabled upnp and now the load average is 0.00 with 97.3% idle. I noticed there are no more freezing in internet access and the downloads don't freeze as well. I enabled upnp again and i saw my load average go back up again to more than 1.00 with 97.3% idle. I came to the conclusion that upnp is causing this issue. I have seen in the threads that people were experiencing the same issue with wrt320n(also a K26 build) but with no explanation as to why. Could you shed some light on this issue? Thanks.