Norton Toolbar Slow Down Typing Response Time in Firefox?

I love the toolbar, but it appears to be an add-on that SEVERELY slows down typing response times, i.e. you type and it takes a few seconds for the letters to appear, I refer to it as a "dramatic pause".   This is VERY annoying and irritating, to the point that I have disabled the toolbar.  Has anyone else noticed this issue?  I am using Toolbar 2012.5.4.6 and Firefox 12.0.  This does not occur in IE only in Firefox.