Setting rake

OK so I have my mast raked back to about 28'5 the shrouds are as low as I can get them and still the rig flops around, it is so loose I worry about it falling? This can not be right huh?, Do need to tighten the forestay even more (there are 3 seperate spacers in there so can shorten it some)? Thanks for the help. Sorry forgot to say I am going for the Snug rig setting