Anthony Morgan

Definitely you can. Go to LSPDFR folder, then open the 'keys' file and change the key for backup menu. If you are not willing to use LSPDFR default backup, set it to 'none' and after that, if you press B while playing UltimateBackup should show up.

You can fix this by either going into the "trainer.ini" file or in-game.
 
TRAINER.INI:
 
Note: You can open *.ini files with a text editor, such as WordPad, Microsoft Word, or the most used NotePad and NotePad++. NotePad++ represents most coding bunches but to be honest, it doesn't really matter, it's your preference.
 
Open up your "trainer.ini" file and look into it.
You must edit a line in the "////DEFAULTS SECTION////".
 
Replace the line
KeyBindingsDisabled=0 //Key Bindings (except menu keys) disabled on startup with
KeyBindingsDisabled=1 //Key Bindings (except menu keys) disabled on startup Or, you can replace your "trainer.ini" file's text with this.
 
INGAME:
 
By going to "Options" page 1, near the end, on the right side of your screen, there is a line that says "Enable/Disable Keys", and toggle that. Note this is temporary, aside from a permanent on-start change with the "trainer.ini" method.
 
 
 
Regards.

The "end call" button is also the car alarm keybind of your trainer.  Go into the trainer's settings and disable keybinds.