Lines going through my blog

I have lines going through my blog. On the side menu and most of my posts. I can’t figure out whats wrong. This problem doesn’t show up on my mac but a lot of my friends that have PCs tell me that there are lines going through my text. Can anyone help me? Please even my web designer can’t figure this one out.

here is the link to where it is happening: blog.aarontbrown.com