This is an example of putting a (B) or © as part of an outline and not getting what was typed or cut & pasted. Instead of the smilie or copyright symbol, a simple "b" or "c" within ( ) is what was typed.
Yes, this is a flaw in the software. We can type (a) and there is no problem. However, if we put a b inside the parenteses, we get an "uncommanded" smiley that appears, as in your example.
The fix? The only thing I can think of is to separate the b and end-parenthesis with a space. Example, (b ). This is the only thing I have come up with so far. Two spaces, ( b ) also works.
For the purists among us, we might also have to do the same to a, as in (a ) or ( a ) for standardization. This whole thing is goofy, but that is the best I can do.