diff --git a/lib/ft8_decode.f90 b/lib/ft8_decode.f90
index 34bce1bf3..7feb5b783 100644
--- a/lib/ft8_decode.f90
+++ b/lib/ft8_decode.f90
@@ -135,6 +135,7 @@ contains
     do ipass=1,npass
       newdat=.true.
       syncmin=1.3
+      if(ndepth.le.2) syncmin=1.6
       if(ipass.eq.1) then
         lsubtract=.true.
         ndeep=ndepth