phranque - 5:31 am on Jul 12, 2013 (gmt 0)
welcome to WebmasterWorld, MrBrightside!
one of the socials bookmarks that i use is down could be that a reason ?
does this affect page load speed?
if so visitors could be bouncing from your site before GA has seen the visit.
your server access logs should tell you how many requests are being made regardless of time spent on pages.