I'm getting the weirdest lag issue while playing D:OS by myself. There is an odd lag/delay to actions related to the interface -- for example when I barter it takes several seconds for items to move to and from the trade screen and for the trade to be accepted; or when I am in dialogue with an NPC it again takes several seconds for dialogue selections to process and the next conversation part to occur -- and this lag often varies from none at all to quite prominent to the point of making the game unplayable.
I have no idea what is going on. I am playing by myself as I have said, so I can't imagine it being a network issue, and yet the problem appears to be akin to playing an MMO with bad network lag. My game performance per se is totally acceptable. I am getting around 100 fps with max settings most of the times.
Please help me figure this out!