If you check on official forums, you will notice that the problem i encountered is common knowledge.
[link removed]
The pads are double triggering, which is a severe design problem, hardware in nature, that will never be fixed by software or firmware update.
More specifically the main part of the controller, the pads, are double triggering or are playing multiple notes during normal usage.
The underlying problem is from the sensors they used (that don't record up and down pressure like on more expensive controllers), the fact that the pads are made from a too hard material and they don't rest on a flat surface, thus triggering multiple notes very easily).
It has been 8 months since the product was launched and they can't fix this problem by firmware / software since it is a physical problem.
It seemed to be such a nice product.
Maybe Atom SQ 2, will have proper pad design and sensors.