diff --git a/src/bpsk/demod.c b/src/bpsk/demod.c
index 71e0fb5..76f303f 100644
--- a/src/bpsk/demod.c
+++ b/src/bpsk/demod.c
@@ -94,6 +94,9 @@ static void make_nco(float32_t *i, float32_t *q)
     }
 
     // XXX MAKE SURE TO DEAL WITH TIMESTEP WRPAPING
+    if (timestep > bpsk_state.nco.samplerate)
+        timestep -= bpsk_state.nco.samplerate;
+
     bpsk_state.nco.offset = timestep;
 }