[Dstar] IC-91AD not transmitting while on the charger???!!!

[Susan Mackay]

I have a 91AD (and very happy with it) but I'm not sure if what I am  
experiencing is normal or a fault in my unit.

I can trigger the local repeater on both high and low power from my  
home. However, when I plug in the battery charger (the standard one  
supplied with the unit by Icom) the transmitted power seems to drop to  
almost nothing.

Using a (admittedly somewhat unproven) field strength meter, without  
the battery charger I get a significant (about half scale) deflection  
on high power and a slight but noticeable deflection on low power.  
With the battery charger in I get a minor deflection on high power and  
nothing on low power.

This is not scientific I know, but is this a 'known' situation with  
the 91ADs, or a known failure mode or am I just unlucky?

Thanks for any information

Susan VK3ANZ