Because you do physically work in SC ("sometimes maybe 1-2 times a month I may do a meeting in SC "), you do have to file a non-resident SC tax return and pay SC for that portion of you salary allocated to the time in SC. GA will tax all your income (even the days in SC) and allow a credit for the small amount you pay to SC.
Ideally, you employer should withhold both SC (a small amount) and GA tax. If they unwilling to do that, you should make quarterly estimated payments to GA to avoid an "underpayment penalty".
