Preview Screen Garbled, extended's very clear??

[doubledkaraoke]

I also am having problems with a garbled preview screen. The bar I work at recently purchased a new PC and upgraded to Hoster 5.07.

ASUS Desktop PC CM1740 Series
Windows 7 with service pack 1
AMD A6-3600 APU with Radeon HD Graphics 2.10 ghz
memory 4 GB
1 TB hard drive

The singers screen is run on the onboard HDMI output through a splitter and amplifier to 3 HDMI TVs. The singers screen is clear and works greats. The preview screen keeps posting lyrics over the top of the old lyrics without clearing first. I have updated all possible drivers on the PC. I can live with the garbled preview screen but would like to get it cleared up. Any ideas?

I only work weekends so any changes would have to wait until the weekend to try.
Thanks