I suffer from blocks like this too, but usually on vowels like E. Sometimes focusing on your enunciation can help. Try hardening those sounds, or softening them, like a softer "g" more like a "j". Another thing would be to speak a little more slowly. I find when I'm talking quickly (which is often) I get hung up more frequently. For me, worst case, a little clearing the throat if I get stuck sometimes gets me over the hump. If you do get stuck, just say "Sorry, I have a stutter." I guarantee the person won't think anything of it, and for you it'll take a lot of pressure off the situation.