diff --git a/fuzzers/030-iob/Makefile b/fuzzers/030-iob/Makefile
index a104b366..56191e3a 100644
--- a/fuzzers/030-iob/Makefile
+++ b/fuzzers/030-iob/Makefile
@@ -5,7 +5,7 @@
 # https://opensource.org/licenses/ISC
 #
 # SPDX-License-Identifier: ISC
-N := 20
+N := 40
 SPECIMENS_DEPS := build/iobanks.txt
 include ../fuzzer.mk