What you describe is not unusual. The 60CSx is an excellent GPSr, but all GPS units have limitations and are affected by a number of variants that can cause confusing results. You don't describe the conditions of where you were at the time, but 30 ft is getting close to the accuracy of the unit.
One suggestion, make sure the compass is turned off by holding the Page button down. The compass does not work if you are holding the unit up at an angle as is typical when walking. I find the compass is handy when I'm within 100 ft or so of the destination, I then turn it on to get a bearing and then off again. I then use the GPS to narrow down the distance. If you use the compass, make sure it is calibrated and make sure you hold the unit flat and level.
I have also found it helpful to stand still for a few minutes when I get close to the cache location to let the unit settle down.
Happy trackin'
thanks for your reply! we were actually in an open area, so should not have been a problem with reception or anything. it's only Day 2 for us as geocachers, so we are still definitely still adjusting and learning, but we love it. I will make sure the compass is off, I think it was, but we'll go back to that same one and see if we can't find it. Thanks!