Multiple instance of same Instrument causes ReferenceError

[TomAuger]

let iA = Gibberish.instruments.PolyFM().connect();
let iB = Gibberish.instruments.PolyFM().connect();

VM17466:5 Uncaught ReferenceError: v_38 is not defined
at eval (eval at generateCallback (index.js:149), :5:28)
at ScriptProcessorNode.Gibberish.node.onaudioprocess (utilities.js:68)

Using same version of Gibberish as on http://www.charlie-roberts.com/gibberish/

(current GitHub version is broken)