Advice needed: Rolex stopping suddenly & regulation

[pereiraex]

Hi guys,

I recently got a new SubC (ref: 116610LN) and I've noticed two main issues:

1. The second hand stops suddenly when the power reserve is close to empty (say 36-48 hours after last use) - now one might reasonably think that it's simply the Rolex not having anymore power reserve to continue running, but no: if I give it a very slight shake it starts running again seemingly as per normal.

2. The watch is running 5 seconds slow on the dial up position - should I send it to regulate? I assume this is free as the watch is still under warranty?

Do let me know what you guys think especially with reference to point 1, are your submariners the same way? I'm hoping there is nothing seriously wrong with the internals and I'll probably get it down to the RSC next chance I get, but would like to hear from you first.