hello!
to avoid zero division at audiorate i use object:
[fexpr~ if($x2==0, 1, $x1/$x2)]

but pd says: fexpr~ divide by zero detected =(

why?
are there other ways to do the same?

Hmm. Guess it's evaluating the second function even though it's not going to output it.

How about
[fexpr~ $x1 / max(1, $x2)]
??

Of course, you can substitute the 1 in there for 0.1, 0.01, etc., according to taste (how close you want to get to the margin, basically).