diff --git a/picard.wdl b/picard.wdl
index 65b26fe29030bd7f993d18fe2daacf9eb576d314..2c638df3bc4ae1d98261393d2f74012c692eb3e0 100644
--- a/picard.wdl
+++ b/picard.wdl
@@ -161,7 +161,7 @@ task SamToFastq {
     String picard_jar
     Float? memory
     Float? memoryMultiplier
-    Int mem = ceil(select_first([memory, 4.0]))
+    Int mem = ceil(select_first([memory, 16.0])) # High memory default to avoid crashes.
 
     command {
         set -e -o pipefail