Slower upload speeds the last few weeks

I recently bought a new computer that has Windows 7 installed on it. I previously used Windows 8. My upload speeds have been significantly slower the last few weeks. My connection maxes out at around 1400 Kbs (11 Mbps) of upload speed. I've not seen it use more than 800-900 Kbs the last few weeks, even with 10 upload slots. I have seen a few individual users download at over 300 Kbs, but the average is around 100 Kbs. It wouldn't have been uncommon to see users download at over 600 Kbs in the past. The amount of bandwidth I have been using has basically been cut in half.

1) My bandwidth appears to be at normal levels when testing at speedtest.net and other sites.

2) I've tried the 11-01 and earlier builds of Qt and NS, but it has no impact on the speed.

3) I've tried different listening and server ports. Windows firewall has been enabled/disabled.

4) The network adapter is a Realtek PCIe GBE Family Controller. I have disabled the Large Send Offload and it has no noticeable impact.

My upload speeds are still pretty good, but they are nowhere close to using my full amount of bandwidth.

Have there been any server side changes that would impact the amount of bandwidth being requested by other clients? I have noticed other users in rooms that used to have similar speed averages have lower numbers the last few weeks as well.

Are there any other Windows 7 or hard drive/USB settings that I can change to fully utilize my upload speeds?