iOS Code Error

[rxlabz]

iOS Code Error

[zinwalin]

remove guard keyword, and make changes to like this:

let inputNode = audioEngine.inputNode

[andrewackerman]

@zinwalin I'm well aware of how to fix the issue. I posted here because it's a standing issue with the codebase that other people will also have to account for and thus should be fixed at the source. (Though judging by the fact that the last commit in this repo was over a year ago, that fix probably isn't going to happen any time soon.)