diff --git a/ares/md/m32x/serialization.cpp b/ares/md/m32x/serialization.cpp
index deb7ec044..d8deba9e5 100644
--- a/ares/md/m32x/serialization.cpp
+++ b/ares/md/m32x/serialization.cpp
@@ -81,4 +81,5 @@ auto M32X::PWM::serialize(serializer& s) -> void {
   s(lfifoLatch);
   s(rfifoLatch);
   s(mfifoLatch);
+  updateFrequency();
 }