Capturing characters in a DataGridView custom column

We have added a user control as an editor in the DataGridView by declaring a class and adding it as a column to the grid. The class is a custom datagrid column implementing the user control which contains a textbox for editing.

When we type characters in this textbox, certain characters are not captured (e.g. lower-case q, dollar sign, exclamation and decimal point).

Has anyone come across this issue or anything similar?