What is your sens set to and more importantly what is your gain is set to? And eve more importantly be advised the stock XS coil is NOT waterproof. That shell is hollow inside, as soon as salt water gets a path to the coil shielding inside the shell the machine will false and be a royal pain in the ass. Repeated salt water exposure will ruin the coil, it corrodes the shield drain wire. I highly recommend you get either the solid epoxy SE coil or the newer SE Pro coil for the beach. Have I mentioned the SE Pro coil is the BEST beach coil!!!!!!!!!
That said I hunt the NJ shore all the time with an Explorer SE and a Pro coil. Here are some thoughts. I run my sens at 26 and my gain at 7, sometimes I drop my gain to 6, depends on falsing. With my sens at 26 the machine is NOT going to sound rock solid quiet like a Sovereign. But with these settings I can get tiny targets, and I mean tiny. I also get DEEEEP targets, I nearly had to call life flight to rescue me last night after digging 4 monsteriously deep holes. Deeper than you would want to dig more than twice in one hunt.
If I want more stability the first thing I will try is dropping my gain. Here's the thing about gain, gain boosts tiny signals and there are plenty of tiny false signals to be had on a NJ beach, a bit of seaweed, foam, tip your coil slightly on the wet sand, reverse direction at the end of your coil too fast, but these false signals compared to a real target like a coin and ring are puny. Out on the beach you get a much stronger signal than inland in the dirt. So what you can do is back off the gain, this won't make the false signals go away, but it will make them so quiet that they are easily ignored. Rings, coins, etc. will still sound off very loud in comparison. The only time I would not want to reduce my gain is when I'm hunting small gold chains but that is slow and tedious so I don't hunt them every time out.
The other thing you have to watch out for on the NJ shore, at least in Atlantic city south to Cape May is the jet black sand, its high mineral content will give the machine a fit. Either go slow and deal with it, or drop your sens, its a tough sand to hunt, its typically worse at the base of a dune after some erosion. I have seen it several inches thick.