[PyQt] speed problem

[Linos]

Hello,
     i have created one pyqt app we are using in my company, it is warehouse application, any fast workers 
seems to be faster that application because of fast bar code scanners, they are introducing items in a 
QTableView with an internal QAbstractTableModel subclass and using QItemDelegate, i am using a python class to 
store the columns in QVariant, every line it is a python object of this class, i have made many profiling and 
fix all the bottlenecks, when they read too fast it is like the return keypress after read the bar code doesnt 
works, i can see in the lineedit of the cell many ean13 codes toguether and it fails to load because it doesnt 
exist. To me it seems like a qt problem because it doesnt close the editor when receive a return keypressevent 
and read the next code in the same editor, i have been to get 4 ean13 in the same lineEdit if i try very fast, 
the machine where i am using the application is a pentium4 1.8 so it should be sufficient to use the app 
correctly, the cpu usage goes on 40% to python, 20% to Xorg, i have tried with psyco and timing the load 
item/create new line python code it is 1.3 times faster than before but i have the same problem with the 
editor, anyone has any idea how i can fix this? other question can i develop a model to the tableview or 
create gui code in c++ and use it from the pyQt application?

Regards,
Miguel Angel.