Word 2011 - Figures/Captions help

[kenno69]

Hey guys, i'm doing my dissertation and have come to the stage where i'm adding captions to images, i've set it up so that the caption is labelled with the chapter with style heading 3 so it should look like this

Figure 5.2.3.a - Shows .....

which is fine, but when i use a caption in a chapter that only is only using heading 2 it looks like this

Figure 6.1.1.a - Shows .....

and it should look like

Figure 6.1.a - Shows .....

But if i set the caption up the other way so it uses heading 2 instead, it shows it like this

Figure 5.2.a - Shows .....

But the actual figure is on 5.2.3.


So basically I want it to go as far down as heading 3 but only if the caption is within a heading 3 section.
I hope i've explained it enough for you guys to understand.
Thanks