diff --git a/malcolm/imalcolm.py b/malcolm/imalcolm.py
index c120c8678..a48c46b12 100755
--- a/malcolm/imalcolm.py
+++ b/malcolm/imalcolm.py
@@ -1,4 +1,4 @@
-#!/bin/env dls-python
+#!/dls_sw/prod/tools/RHEL6-x86_64/defaults/bin/dls-python
 
 
 def make_process():
@@ -128,6 +128,8 @@ def main():
     import os
     import sys
 
+    os.environ["EPICS_CA_MAX_ARRAY_BYTES"] = "6000000"
+
     sys.path.append(os.path.join(os.path.dirname(__file__), ".."))
 
     from pkg_resources import require