In circa 2014 there was a batch of Shapeshifters that were built with power entry fuses that were slightly off in value. This created an issue for some users where their Shapeshifter would randomly power off.
To fix the problem you needed to either replace the fuses with higher spec ones:
Bournes MF-MSMF030-2 PTC RESETTABLE .30A 30V 1812
or bypass them by soldering a little wire across them.
Fortunately the fuses are easily accessible from the side of the module as seen in this pic.