I have had a similar problem in those areas as well as south of Gull Shoals. I had one of those anchors that has the rode attachment ring that slides down the anchor shaft to the flukes making it easier to retrieve. Seems it was turning over and was on the bottom in the retrieval position. Worked almost every time that I left it down in the right position slowly until contact with the bottom was made then continued to leave out line slowly for another 20ft or so before feeding the rode out in a more timely fashion. An oldtimer said the chain would carry the ring down the shaft of the anchor to the retrieval position if left down to fast. I replaced it with a standard danford type anchor and have had few issues since then. The only reason I replaced it was because I always seem to be in a hurry to get anchored and get to fishing.