Looks like the same size to me, but the spacing is different.
AdRotate sets a spacing and lineheight for it’s groups.
Some broken/poorly coded themes interpret that limit as to use it for everything.
In pretty much all cases before, the theme was wrong and needed a fix. Either to set their own spacing or lineheight, or to set it in a different way so that whatever plugins do does not affect your content.
Check with your theme maker for details on how to do that 🙂