Had the same issue a couple of years ago.....but the cause for me was the 120v heating unit on my water heater. Evidently, this causes this problem on a regular basis. If you have a gas/electric water heater, it's worth checking out ad easily fixed.
A fault in the water heater cannot cause a non-hazardous tingle between an RV and earth ground. The only thing indicated by a non-hazardous tingle is an ungrounded RV chassis. A water heater fault combined with an ungrounded chassis creates a very hazardous situation, which is why a good ground connection is so important. The water heater fault will however cause a shore power GFCI to trip when the chassis is properly grounded.
If you have a "hot" chassis there's a grounding problem. There may or may not be an additional problem on top of that.
