diff --git a/asQ/preconditioners/circulantpc.py b/asQ/preconditioners/circulantpc.py
index 4ac1bf76..bccb89db 100644
--- a/asQ/preconditioners/circulantpc.py
+++ b/asQ/preconditioners/circulantpc.py
@@ -265,6 +265,8 @@ def initialize(self, pc):
 
             self.block_solvers.append(block_solver)
 
+        self.first_solve = True
+
         self.initialized = True
 
     @profiler()
@@ -360,6 +362,9 @@ def apply_impl(self, pc, x, y):
 
         # Do the block solves
 
+        if self.first_solve and self.ensemble.ensemble_comm.rank > 0:
+            self.ensemble.global_comm.Barrier()
+
         with PETSc.Log.Event("asQ.diag_preconditioner.CirculantPC.apply.block_solves"):
             for i in range(self.nlocal_timesteps):
                 # copy the data into solver input
@@ -377,6 +382,14 @@ def apply_impl(self, pc, x, y):
                 cpx.get_real(self.block_sol, self.xfr[i])
                 cpx.get_imag(self.block_sol, self.xfi[i])
 
+        if self.first_solve and self.ensemble.ensemble_comm.rank == 0:
+            self.ensemble.global_comm.Barrier()
+
+        if self.first_solve:
+            self.ensemble.global_comm.Barrier()
+
+        self.first_solve = False
+
         ######################
         # Undiagonalise - Copy, transfer, IFFT, transfer, scale, copy
         # get array of basis coefficients