[senit] power for trackerball plus

We have been experiencing a problem with the use of portable computers and  
joystick/trackerball plus.  The XY lock will come on.  It appears from  a 
conversation with Traxsys that this is a problem with power from the usb  port.  

QUOTE from Traxsys  response. 
'The fault appears because newer  laptops are lower powered than slightly 
older ones and can provide less than 5V  for a USB mouse, sometimes it can be as 
low as 4.3V.  The device in  question needs 5V to work correctly.' 
Does anyone have a solution to  this problem as we have many users who rely 
on the use of their  trackerball/joystick plus for access? 
Trish  
CENMAC 