Subreports not showing !!

Hello,

I have been hitting my head over the table for several hours on this problem ...

I have a master report called Report A. Report A has 8 subreports and several buttons, which are controlled by 3 parameters (drop downlist) from the user. Parameter 1 filters parameter 2, these parameters (1 and 2) are independent of parameter 3. If the user selects one option from the drop-down of parameter 3, then the report should render one of the eight subreports, passing parameters 1 and 2 into the activated subreport to generate graphs. For some options in parameter 3, i can easily render the subreport, but for other subreports, i can not! The odd thing about my issue is that I do not see these problems when I open an individual subreport and manually select parameters 1 and 2 from its drop-down menu; the report (subreports) by themselves seem to work perfectly, accessing them from Report A is the problem. Please, anyone, give me your suggestions. If you are confused, let me know so that I can explain more clearly.

Thanks,