what could be causing gaps between text in posts

possibly the 10px margin below the post image combined with the line height of the text; as styled in style.css of your theme:

.post_thumbnail {
    padding: 6px;
    background: #FFFFFF;
    border: 1px solid #DFDDD5;
    margin: 0 10px 10px 0;
}

you might need to post a screenshot to point to the exact spot of the problem.

or try to align the image to the right to see if that loks different.

general more a formatting problem which is not within the scope of this WordPress forum;

try to work with a tool such as Firebug https://getfirebug.com/ to identify the cause.

Hi alchymyth,

Thank you for your help, heres a link to a screen shot of the same page I linked to earlier. I have marked where the problem in the posts normally occurs.

https://www.dream4mobiles.co.uk/imagesnew/blog.png

your posts formatting seems to be set to text-align: justify; and if there is not enough space to fit another full word, you will get those kind of gaps.

change to: text-align: left;

the existing code in style.css:

.entry {
	text-align: justify;
	line-height: 18px;
	padding-top: 8px;
	font-family: Arial, Helvetica, Sans-serif;
	font-size: 13px;
    color: #555555;
	}

Thanks for that ill give it a go