Hi. I have noticed big elevation problems while recording in MTB mode on my Garmin Instinct. My wife’s Fenix 5S showes 48m elevation and my Instinct shows 200m for same ride.
Yesterday, during a 51-minute, 3.8-mile walk, my Instinct trackd an elevation gain of 3,152 feet! The elevation graph is fine for about 8 minutes and then turns into a jumble of spikes -- with several going below sea level! The range of elevations is from about 300 feet below sea level to 300 above sea level. My actual route was about 180-200 feet above sea level.
