Layer Shows through even when frozen in VP

Recently we were asked to label each tab in an instrumentation diagram using text. When inputting the text labels, we make sure that it is only viewable in the layer it is associated with. However, when we try to use another viewing program, every single tab label shows through on each tab. This as you can imagine creates quite the mess and we have not been able to figure out why.

Furthermore, it only does this to certain drawings. Could this be a problem with our version of AutoCAD Mech 2008?

when we try to use another viewing program, every single tab label shows through on each tab.

Another viewing program?

Sounds like an issue with the viewing program, not with Autocad.

The program is called Fastlook 12. We have already had several problems with our version of AutoCAD, highlighted layers always go to the back when we want them to stay in the front. We can't get X-refs to bind to original drawings, title blocks going missing, to name a few more problems. Believe it or not Fastlook actually corrects some of these problems when viewing, so I doubt it is an issue with that end. Up until now we have been able to get around the problems we have had with AutoCAD, but this one is definately an issue with AutoCAD and we cannot figure it out.