Inconsistent RT-PCR results - (Aug/09/2005 )

I am doing RT-PCR for 5 samples. After finishing my RT part, I did PCR in duplicates for each sample. I was surprised to find out that each pcr reaction from same sample gave different results. For PCR part, I prepared master mix so that conditions are same in each case. I apprecaite your help.

I think this inconsistence can only be attributed to technical errors, such as uneven mixing of the master mix, uneven mixing after adding the template, different amplification efficiency of cycler's wells, and uneven lighting of the gel box.