It is hard to be successful with calls in FL, especially on public land. The whole reason bucks respond to calls (rattling, grunts, snort wheezes) in the first place is their fear that another buck has came into his area and trying to steal his poon, basically outside competition trying to breed his does. In FL (especially public land) there are very poor buck to doe ratios and the bucks rarely have to fight and protect their soil since there is enough does to go around for the whole buck herd on the given property. Also, with poor buck to doe ratios, the bucks have the convenience of chasing/tending/breeding on their own time and rarely have to move in daylight hours to search for does (probably why you haven't heard many deer noises while in the stand, a bucks going to do what makes him most comfortable in a low buck to doe ratio property)
I've had best luck using calls when the bucks signs tell you he's hunting for does (active scrapes, fresh rub lines, or if your lucky enough to see a buck chasing). Still use calls very sparingly during the time you consider "the rut". The worst mistake any FL hunter could do is grab a set of rattling horns and bash them together, that works on TV when hunters are after 150"+ bucks but in FL the deer would know a fight that loud is unnatural or they are about to get their ass whooped, either way they will take off running. after all, our mature public land bucks are very smart and didn't get old by coming to the first grunt call he heard.