Destructor problems

Hi all,
I made a class called TV0 to store some results from a fit but I'm experiencing some problems with it's destructor. When I use it, I create a TV0 *tmpV0 = new TV0() and if some cuts are not passed I delete the new instance (delete tmpV0). ROOT crashes with a segmentation violation referring to the dtor:

0x04e6f1ce in TV0::~TV0 [in-charge deleting]() at
/home/mussini/Run2Analysis/K0sL0/TV0.hh:57 from
/home/mussini/Run2Analysis/K0sL0/TV0_cc.so

I tried several ways to fix this issue but without succeeding! Inside the class no "new" instances are created so the destructor is simply: ~TV0() {}

I know that these few infos could not be enough to understand the problem but ... any idea about where can I start looking at? There could be a BIG and obvious mistake that I'm not able to find! :-))) I've attached the class interface.

Bye...