From 989dc0aabe4111891049fa5fadf4c857dfde8d6c Mon Sep 17 00:00:00 2001
From: Felix Roos <flix91@gmail.com>
Date: Sat, 16 Sep 2023 01:33:09 +0200
Subject: [PATCH] fix: filters without envelopes

---
 packages/superdough/helpers.mjs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/superdough/helpers.mjs b/packages/superdough/helpers.mjs
index 92f670d9..32ca0bb2 100644
--- a/packages/superdough/helpers.mjs
+++ b/packages/superdough/helpers.mjs
@@ -98,7 +98,7 @@ export function createFilter(
   filter.frequency.value = frequency;
 
   // Apply ADSR to filter frequency
-  if (fenv !== 0) {
+  if (!isNaN(fenv) && fenv !== 0) {
     const offset = fenv * fanchor;
 
     const min = clamp(2 ** -offset * frequency, 0, 20000);