I had this issue with my Model 3, so I'm not certain if the situation is the same with the Model S.
For 2 years my navigation was dead on, then came the update that enabled the cabin camera and BOOM... the car was intermittently displaying as driving on the side of the road (worse actually, it would've been driving through houses and on front lawns). It was generally accurate, just maybe 15 feet offset from it's actual position... and again this was an intermittent issue.
I read forum posts from a few owners confirming that they had similar issues and that it was caused by EMI (electromagnetic interference) from the camera wiring.
The GPS antenna in your car needs a signal from a GPS satellite (three, actually). These satellites are NOT geostationary, so they're in motion at all times. Additionally, your car is turning in various directions at all times.
Now add one wire next to your GPS antenna that adds a bit of noise (radio interference) to the mix. What this does is that sometimes, your GPS antenna is able to get signals from 3 or more satellites, but all it takes is for you to turn (or one of the satellites to move) whereby the camera wire is *between* your GPS antenna and a satellite and BAM!... the car thinks it's 20 feet further west than it actually is.
I pointed the service center at a forum post here where an owner confirmed that his service center resolved the issue by replacing the camera, but they replaced my GPS antenna and said they confirmed it was fixed. Picked up the car, not fixed. My guess is that they tested it in the parking lot, saw the offset issue, replaced the GPS antenna, tested again and the offset was gone. BUT... shuffling the wires around would certainly change the "direction" of the problem.
On my second visit, they replaced the camera. STILL didn't fix it. 1.5 hours each way plus wait time. Zzzzzz.
Third time's the charm! On my third visit they replaced the wiring harness. Bingo. Problem solved.
Now I'm not saying it's always the wiring harness (or even which harness), perhaps for your situation it's different... but for me, that did the trick. If this problem began after they enabled the cabin camera though, then most certainly that's what's causing it (EMI from a cabin camera or it's wiring).
The symptom was that not only was the car intermittently offset from it's real-world position, but the nav directions would constantly tell me to "turn right onto main street", "turn right onto main street" each time I crossed a side street (I was already on main street). When this occurred, it made the navigation very difficult to trust. Not so bad when you're at home and know your way around. Very bad when you go out of town to a large city with a confusing network of roads.
Even if you're out of warranty, I would strongly suggest you let them know this started when the cabin camera was enabled (if that's true) and press for this to be covered.
I hope this helps. Good luck!!
