SSRS Header (Fixed) is displaced when scrolling left to right

Hi,

I'm using Report Builder 3.0 for my SSRS.  have a tablix report where I would like to have my row and column header fixed. I fixed the column header using the RowGroups>AdvancedMode>Static> Fixed Data True, KeepGroup After, RepeatHeader True then FixedRowHeaders True for my row header. The headers are fixed ihen scrolling down in Report Builder although the row header overlaps when scrolling to the right.

In the web report, I have no problem scrolling down but when I scroll down then right, the rows in my header are displaced.

Also I have 2 horizontal and vertical scroll bars which is a pain since I have to scroll down first before I can scroll right. 

I would really appreciate any help.

Thanks a lot,

Cielle