Does anyone have any circulation problems with their feet while using a hammock? I inevitably end up with a bit of sag in the hammock, no matter how taut I get the ridgeline. This causes my legs to be slightly elevated from my hips, and consequently I'll often wake up with cold feet because I'm not getting enough cirulation to my feet. Has anyone encountered this, and if so, have you found a solution? Hopefully I'm just doing something wrong with pitching the hammock. For the record, I pitch it with a level ridgeline and sleep as diagonally as I can.