Seems more like fall distance related to me. Long enough fall and you can damage your boat or break your surfboard in real life.

If you were moving at top speed, with a good wind on calm waters: Could it be a fish hitting the hull?
*edit* or more correctly, you ramming the fish ;)

I noticed going forward you have One, Two, Three arrows that indicated speed. Did you notice that the arrows turn red when at three? I always thought maybe that meant your boat is going faster then what is deemed 'safe' and it 'could' take damage. /shrug. But who knows.

If the boat is in what you think is deep water but close to shore AND there is a severe storm, that up and down action is liable to bounce the keel off the bottom.

Originally posted by Weaver:

If you're on a server it's typically a sinc issue.

As long as it doesn't turn into a sink issue...... :-)

A rock, shallow water, or a log can all damage your boat if you don't see them which is easy at night along the coast, in fog or in storms, heck even offshore it can happen.
In storms, waves can knock people off and do damage to the hull based off of it flying in air and slamming into water.

No bugs here. :)

I think Weaver has this right because it's not something that relates to rocks, shallows, storms, or boats looking like they're hitting waves any harder than usual. We're just sailing along over calm ocean with a good wind and occasionally *crack* there's a single ten damage ping from nowhere and nothing.

Originally posted by Weaver:

If you're on a server it's typically a sinc issue.

I'm personally upping this, used to have that happen all the time when playing with friends, not a single time again since i was left alone :(

Originally posted by us271934:

As long as it doesn't turn into a sink issue...... :-)

https://www.youtube.com/watch?v=6DC9xez5pxU

So it's likely some of the crew being *really bad* pillion passengers? That does check out, with our server being in Scotland and half the gang being Australian.

If it's an idle boat and it's taking random damage then it's possible a leach got inside it's mesh. I had this happen once, I rammed the ship on land in order to break and rebuild it but the leach fell out.

If you're on a server it's typically a sinc issue.

I always find underwater rocks that hit the bottom when the swell ebbs when close to shore, either anchored or sailing past. Sometimes Necks if anchored too close will swim out. Even seen a boar chewing at my hull when I anchored way too close ... lol.

I used to have that happen in multiplayer, but not in a long time.

Waves more than likely? Or where it's simply too shallow?

I think it has to do with rough waves, or the boat "slamming" into the water too hard during lag spikes.