This fix applies to the following themes: Clip Cart 1.5.3 and lower, ReadyFolio 2.2.5 and lower, Quik 1.3.4 and lower used with Genesis 2.2 and higher.

If when you view your mobile menu the text is all jumbled together or missing then edit style.css included with the above themes and search for:

#mobile_menu_area #pull span {

and change it to:

#mobile_menu_area #pull > span {

When you clear your cache (if necessary) and reload your site, your mobile menu should be working correctly again.

Props to our users for noticing this: andrea & martin_metzmacher for a suggested fix.