diff --git a/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/apertif_unb1_correlator.vhd b/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/apertif_unb1_correlator.vhd
index ba75d73d53322b6cfc4e379d0d4ebade76ce317e..8778b15f9e2e5416366071d97ebb012bff92a63c 100644
--- a/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/apertif_unb1_correlator.vhd
+++ b/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/apertif_unb1_correlator.vhd
@@ -130,11 +130,17 @@ ARCHITECTURE str OF apertif_unb1_correlator IS
   CONSTANT c_complex_data_w         : NATURAL := 8;
   CONSTANT c_conjugate              : BOOLEAN := TRUE;
   CONSTANT c_nof_channels           : NATURAL := 64;
-  CONSTANT c_integration_period     : NATURAL := sel_a_b(g_sim, 0, 12208);
+  CONSTANT c_integration_period     : NATURAL := sel_a_b(g_sim, 0, 12207);
   CONSTANT c_nof_visibilities       : NATURAL := (c_nof_inputs*(c_nof_inputs+1))/2;
-  -- . With no inter channel output delay, channels are output back-to-back, creating a short full valid burst 64 channels (12.8 Gbps).
-  --   We need to set an appropriate number of inter-channel delay cycles to even out the correlator output duty cycle.
-  CONSTANT c_inter_channel_delay    : NATURAL := 0;
+  -- . Inter Channel Delay:
+  --   . With no inter channel output delay, channels are output back-to-back, creating a short full valid burst of 64 channels (12.8 Gbps burst, 158Mbps on average).
+  --     We need to set an appropriate number of inter-channel delay cycles for a constant visibility buffer output rate.
+  --   . The total accumulator output rate = (150 streams*200MHz / 12207) = 8192.021 channels/sec (157Mbps)
+  --   . 8192 channels/sec = 128 * 64 channels * 300 visibilities
+  --   . No   inter channel delay: 128 * (19200 valid cycles + 1543300 invalid cycles =)          1562500 cycles/sec = 200M        cycles/sec
+  --   . With inter channel delay: 128 * 64 channels * (300 valid cycles + 24114 invalid cycles =)  24414 cycles/sec = 199.999.488 cycles/sec (less than 200M so we're fast enough)
+  CONSTANT c_inter_channel_delay    : NATURAL := sel_a_b(g_sim, 4400, 24114); --                    ^^^^^--- 24414= 2*integration period.
+                                                                              -- 4400=~5.5x faster than 157Mbps = 860Mbps burst for sim (but still 157Mbps on average)
 
   -- WPFB
   CONSTANT c_wpfb_wb_factor         : NATURAL := 1;                    -- = default 1, wideband factor