diff --git a/lib/decoder.f90 b/lib/decoder.f90
index 59f80b4c0..0b12d020d 100644
--- a/lib/decoder.f90
+++ b/lib/decoder.f90
@@ -687,12 +687,14 @@ contains
 
     write(*,1001) params%nutc,snr,dt,nint(freq),decoded0,annot
 1001 format(i6.6,i4,f5.1,i5,' + ',1x,a37,1x,a2)
-    if(ios13.eq.0) write(13,1002) params%nutc,nint(sync),snr,dt,  &
-         freq,0,decoded0
-1002 format(i6.6,i4,i5,f6.1,f8.0,i4,3x,a37,' FT4')
+
+    if(ios13.eq.0) then
+       write(13,1002,err=10) params%nutc,nint(sync),snr,dt,freq,0,decoded0
+1002   format(i6.6,i4,i5,f6.1,f8.0,i4,3x,a37,' FT4')
+       flush(13)
+    endif
     
-    call flush(6)
-    if(ios13.eq.0) call flush(13)
+10  call flush(6)
     
     select type(this)
     type is (counting_ft4_decoder)