Suunto computers have what I call a nanny function; they always calculate your oxygen loading and MOD at the next higher integer percentage to the one you've set. This is explicitly stated in the manual. This isn't a problem if you're actual FO2% is XX.5% or higher, but is a pain if it's XX.4% or below. In the latter case, in order to get the same MOD result as a table you have to set the computer for the next lower FO2%. Example, if your FO2 analyzes 32.2% and you set the computer for 32%, it will do all calculations and give you MOD for 33%. Which is why it gives you a result of 127' and not 132' for EAN32 @ 1.6 PO2.
Your SSI dive tables should show MOD @ 32%/1.6 as 132', not 135'. If you look in the SSI Nitrox manual, there should be a table (in Chapter 2 IIRR) which lists MOD for PO2s of 1.3 to 1.6. And as others have mentioned, it's considered a good idea to use a working PO2 max. of <=1.4 rather than 1.6.
Guy