It sounds like your problem might be due to incorrect or missing MIME types (for the font files) on your web server.
If this is the case, then you may have to contact your web host to ask if they can add the font file types (.eot, .svg, .ttf, .woff) to the list of MIME types (so that browsers know what to do with them).
Also, try viewing your gallery in different browser to see if the problem occurs in them all or just in certain browsers.
For example, if you see the problem in just Internet Explorer, then make sure that Compatibility View is not enabled.
I hope these notes help.
However, if you continue to experience difficulties, please post the URL to your gallery's web page so that I can take a look at the problem and hopefully help further. Thank you.