I'm encountering a new (to me) mining glitch on this one Minecraft server. The owner isn't having the problem, but the server is in the same city as where he lives, so it may be communication relay related, but I don't think so.

If I mine a single block (like with an unenchanted iron pickaxe), it seems to work correctly pretty much all the time.

If I hold down left click and try to mine multiple blocks in sequence, then other blocks besides the first will often keep reappearing. Eventually, they'll get mined, although the quickest solution is to let go of the button and then mine the block in isolation.

I've found one similar bug, MC-51915, but my report is NOT a dupe of that bug. In that other case, there is some server lag, even in single player mode, that is making the server take excessive time to make the block drop as an item.

However, on this server, we're not experiencing any server CPU load issues, and communication latency seems to be really fast and also not a bottleneck. I can wait as long as I like, and the block will never drop as an item. Basically, the mining just failed or got lost for some reason, and I have to try again.

I don't have any privileged access to this server, but I can talk to its owner so as to acquire as much diagnostic info as you'd like. Can I turn on something on the client that logs individual client/server messages and paste on the ones related to mining failed blocks?

Thanks!