Hmm - that doesn't sound right. Some mods will just say 'Low Battery' when the cells get weak (say 3,2-3,3V or so) and some will decrease the vape power until cutoff (my SXK Zeroes do this). I'm not sure how the Cuboid behaves.
The RX200 is a very good mod, especially when used with an external charger - the Cuboid is well thought of, you may have just gotten a lemon.
The RX200 is a very good mod, especially when used with an external charger - the Cuboid is well thought of, you may have just gotten a lemon.