diff --git a/src/as/asCa.c b/src/as/asCa.c
index 9ac266521..c205d34d5 100644
--- a/src/as/asCa.c
+++ b/src/as/asCa.c
@@ -175,7 +175,7 @@ LOCAL void asCaTask(void)
     int		status;
 
     taskwdInsert(epicsThreadGetIdSelf(),NULL,NULL);
-    SEVCHK(ca_context_create(enablePreemption),
+    SEVCHK(ca_context_create(enablePreemption,1024),
         "asCaTask calling ca_context_create");
     SEVCHK(ca_add_exception_event(exceptionCallback,NULL),
         "ca_add_exception_event");