Problems with ST60 Tridata!!

[searay495]

I am unable to set my shallow alarm below 10 feet. I can raise the limit, but not lower it. I did a factory reset and no luck....Does anyone have any ideas? I have seemed to stump the staff at Raytheon. They can't offer any suggestions.
It is an older unit....about 7 years old.
Please help:huh::smt009