Thanks for posting your question. The engineering team was recently made aware of this strange behavior and has spent some time over the past two weeks attempting to reproduce it. So far we have not been successful.
What we do know is that it appears the default value for the contrast is errantly getting set to 0% upon power up. Until we can resolve this bug the contrast can be reset to the default value of 33% by:
1) Press menu/exit
2) Turn either encoder clockwise until you can read 33%.
3) Press menu/exit
Your experience is valuable as we try to resolve this issue. Can you answer the following questions?
1) What is the serial number of the unit(s) of interest?
2) What is the firmware revision for the USP3T and display? (This information can be found in the "monitor" menu.)
Once again, thanks for posting. If you have any additional questions or concerns please feel free to contact me via phone through tech support.
Program Manager XTi/CDi/DSi, ITECH