If the pain is near the port, it is not a slip. The distance between the band itself as it goes round the stomach is quite large, the connecting tubing length depends on the type of band but can be as much as 10cm. Chewing, or lack of it, is not going to make the port area sore.
The usual sign of a slip is extreme tightness, so that swallowing anything becomesa painful or even impossible. Occasionally, if the band was not sutured in the first place (and that would be surgical error) it can slide upwards and go round the oesophagus and then you would lose all restricition.
People who get pain near the port site often find it is a pulled muscle. Also, because the port is hard, as we lose weight and there is less fat, we can bump it and make a bruise! I've done that several times.
Rarely (and this really is rare) is that the port site becomes red and inflamed (not connected to the surgery and healing) and this is serious as it may be a sign of erosion. Infection develops round the stomach and travels along the band tubing (exterenally, it is a sealed unit). But erosion really is unusual.
But if you get any unexplained pain which does not go after a day or so, always ask your doc.
Highest 290, Banded - 248 Lowest 139 (too thin!). Comfort zone 155-165.
Happily banded since May 2006. Regain of 28lbs 2013-14. ALL GONE!
But some has returned! Up to 175, argh! Off we go again,