ASP.NET Variables all mixed up [Intermitten problem]

Greetings,
I have created a web application on Windows 2008 Server
It was working fine but lately there are some weird errors happening to it and the worst thing is that it is an intermittent error.
For some reason, the values from variables are getting mixed up.
I created a test and below is an example of what i found out when the intermittent error happens... otherwise the values are okay.
string test = "AltVal";
lblTest1.Text = "ALT VAL1 -- " + db.GetDBValue(test);
lblTest2.Text = "ALT VAL2 -- " + db.GetDBValue("AltVal");
If you look at the code closely.  Both should give the same value.  GetDBValue is a function call to get value from the database.
But the result is different.  lblTest1.Text is returning the right value while lblTest2.Text is returning wrong value.
But I don't understand what might have caused the value in the db.GetDBValue("AltVal") to be wrong because db.GetDBValue(test) s ...