Misc ingredient amounts

I added two new ingredients in the Misc category of the Ingredients profile. The amounts were set to 5 and 1. When I go to add the ingredient to a recipe, the 'Add Misc' modal comes up and lists the ingredient, but the amounts are 5.5 and 1.1 instead of the 5 and 1 I had entered when creating the ingredient profile.

I added another ingredient to test and set the amount to 3. When adding the ingredient, the amount was 3.3.

Additional info...
ingredient type: Spice
Unit for amount : oz

When you added the spice to the misc items profiles, you keyed in the amount you wanted to add.  The line under that is 'for batch size of'.  Check that amount to see if it is the same as your standard batch size.  It is most likely that the amount is set for a batch size of 5 gal and you are brewing something on the order of 5.5 gal.  When you add an ingredient to your recipe, BeerSmith scales the standard amount based upon the setting in your ingredient profile.

+1 to Oginme's advice.

If you want an ingredient addition to always be the same amount no matter what batch size, set the batch size field to zero.