diff --git a/src/runner_doiact.h b/src/runner_doiact.h
index 517edad63abdeee4a3ce0170d8808254d03aeb12..599473e1d8f885613d2c2faeed26f7cc12a5fd22 100644
--- a/src/runner_doiact.h
+++ b/src/runner_doiact.h
@@ -1819,9 +1819,9 @@ void DOSUB1 ( struct runner *r , struct cell *ci , struct cell *cj , int sid ) {
         
             /* Do any of the cells need to be sorted first? */
             if ( !(ci->sorted & (1 << sid) ) )
-                runner_dosort( r , ci , (1 << sid) , 0 );
+                runner_dosort( r , ci , (1 << sid) , 1 );
             if ( !(cj->sorted & (1 << sid) ) )
-                runner_dosort( r , cj , (1 << sid) , 0 );
+                runner_dosort( r , cj , (1 << sid) , 1 );
         
             /* Compute the interactions. */
             DOPAIR1( r , ci , cj );
@@ -2099,9 +2099,9 @@ void DOSUB2 ( struct runner *r , struct cell *ci , struct cell *cj , int sid ) {
         
             /* Do any of the cells need to be sorted first? */
             if ( !(ci->sorted & (1 << sid) ) )
-                runner_dosort( r , ci , (1 << sid) , 0 );
+                runner_dosort( r , ci , (1 << sid) , 1 );
             if ( !(cj->sorted & (1 << sid) ) )
-                runner_dosort( r , cj , (1 << sid) , 0 );
+                runner_dosort( r , cj , (1 << sid) , 1 );
         
             /* Compute the interactions. */
             DOPAIR2( r , ci , cj );