Lag for one of two people on same IP

[lindz]

My husband and I have been duoing on our monk/shaman and the last few days I have been getting lag such that my character takes up to two minutes to react to commands I have just given her or move to someplace I have just moved her. My latency is fine, remaining steady at 115-125 ms throughout.

My husband is not having these problems at all.

It began on sunday in the Karanas and has been happening since, in different locations. I relog, it is fixed for awhile then comes back full swing. Last night it was as bad as within 5 minutes of relogging/rebooting.

Any idea what could be causing just one of us this awful lag?