diff --git a/.testing/Makefile b/.testing/Makefile
index 1946b133d0..59bf91d6d8 100644
--- a/.testing/Makefile
+++ b/.testing/Makefile
@@ -559,7 +559,7 @@ $(eval $(call STAT_RULE,repro,repro,,,,1))
 $(eval $(call STAT_RULE,openmp,openmp,,,GOMP_CPU_AFFINITY=0,1))
 $(eval $(call STAT_RULE,layout,symmetric,,LAYOUT=2$(,)1,,2))
 $(eval $(call STAT_RULE,rotate,symmetric,,ROTATE_INDEX=True\nINDEX_TURNS=1,,1))
-$(eval $(call STAT_RULE,nan,symmetric,,,MALLOC_PERTURB_=256,1))
+$(eval $(call STAT_RULE,nan,symmetric,,,MALLOC_PERTURB_=1,1))
 $(eval $(call STAT_RULE,dim.t,symmetric,,T_RESCALE_POWER=11,,1))
 $(eval $(call STAT_RULE,dim.l,symmetric,,L_RESCALE_POWER=11,,1))
 $(eval $(call STAT_RULE,dim.h,symmetric,,H_RESCALE_POWER=11,,1))