Hard to say without the logs, but my first guess would be the PSU.
The R-PI is really sensitive to the supply voltage. Although it is usually said to need 5 to 5.2v, my experience is that it really needs to be much more like 5.2 than 5v.
Trying to fix these problems (for non shake use) I ended up buying several PSUs, all reputedly capable of delivering 5.2v @ 2.5A. Turns out that tends to be a bit of an exaggeration for a lot of the cheap Chinese PSUs. Also, 2.5 really is minimal for the R-Pi, especially the later versions. I would call 3A really the minimum requirement.
Another problem is the quality of the USB cables to connect them. No matter how much you pay, how well constructed they appear to be, al LOT of these really are not up to carrying 2.5 or 3A. I ended up buying one of those USB voltage/current meters and a variable USB load and testing quite a few different cables before I found some that were up to the job. Once you get beyond about three feet in length, very few are.
Where longer runs are required for the power cable, I recommend thinking about using a coverter module, very close to the R-Pi (with a few feet) and running 12v (or maybe more) to deed that over the longer distance.
I used this:
There is a discussion on the results here:
All that said, my Shake-Boom has worked very reliably with the provided PSU fed from an Uninterruptible PSU.