diff --git a/map65/libm65/decode0.f90 b/map65/libm65/decode0.f90
index acc5bc228..f7fa82d8e 100644
--- a/map65/libm65/decode0.f90
+++ b/map65/libm65/decode0.f90
@@ -55,7 +55,6 @@ subroutine decode0(dd,ss,savg,nstandalone)
        mousedf,mousefqso,nagain,ndecdone,ndiskdat,nfshift,ndphi,           &
        nfcal,nkeep,mcall3b,nsum,nsave,nxant,rmsdd,mycall,mygrid,          &
        neme,ndepth,hiscall,hisgrid,nhsym,nfsample,nxpol,nmode)
-
   call timer('map65a  ',1)
   call timer('decode0 ',1)
 
diff --git a/map65/libm65/filbig.f90 b/map65/libm65/filbig.f90
index 92a489237..4fc3e3b62 100644
--- a/map65/libm65/filbig.f90
+++ b/map65/libm65/filbig.f90
@@ -73,7 +73,7 @@ subroutine filbig(dd,nmax,f0,newdat,nfsample,xpol,c4a,c4b,n4)
 ! When new data comes along, we need to compute a new "big FFT"
 ! If we just have a new f0, continue with the existing ca and cb.
 
-  if(newdat.ne.0) then
+  if(newdat.ne.0 .or. sum(abs(ca)).eq.0.0) then  !### Test on ca should be unnecessary?
      nz=min(nmax,nfft1)
      do i=1,nz
         ca(i)=cmplx(dd(1,i),dd(2,i))
diff --git a/map65/libm65/map65a.f90 b/map65/libm65/map65a.f90
index fd28fab3c..96b2ba233 100644
--- a/map65/libm65/map65a.f90
+++ b/map65/libm65/map65a.f90
@@ -31,7 +31,7 @@ subroutine map65a(dd,ss,savg,newdat,nutc,fcenter,ntol,idphi,nfa,nfb,        &
   data shmsg0/'ATT','RO ','RRR','73 '/
   data nfile/0/,nutc0/-999/,nid/0/,ip000/1/,ip001/1/,mousefqso0/-999/
   save
-
+  
   mode65=mod(nmode,10)
   if(mode65.eq.3) mode65=4
   mode64=nmode/10
@@ -258,7 +258,7 @@ subroutine map65a(dd,ss,savg,newdat,nutc,fcenter,ntol,idphi,nfa,nfb,        &
               endif
            endif
         endif
-     enddo
+     enddo  !i=ia,ib
 
      if(nqd.eq.1) then
         nwrite=0
@@ -343,8 +343,8 @@ subroutine map65a(dd,ss,savg,newdat,nutc,fcenter,ntol,idphi,nfa,nfb,        &
            write(*,1012) mousefqso,nutc
 1012       format('!',i3,9x,i6.4,'  ')
         endif
-   
-     endif
+     endif  !nqd.eq.1
+
      if(ndphi.eq.1 .and.iloop.lt.12) then
         iloop=iloop+1
         go to 2
diff --git a/map65/libm65/q65b.f90 b/map65/libm65/q65b.f90
index 9da1b8430..7b7dfcf08 100644
--- a/map65/libm65/q65b.f90
+++ b/map65/libm65/q65b.f90
@@ -92,7 +92,8 @@ subroutine q65b(nutc,nqd,fcenter,nfcal,nfsample,ikhz,mousedf,ntol,xpol,  &
      if(ipol.eq.3) cz(0:MAXFFT2-1)=cy
      if(ipol.eq.4) cz(0:MAXFFT2-1)=0.707*(cx-cy)
      cz(MAXFFT2)=0.
-     call four2a(cz,2*nfft2,1,1,-1)     !Transform to time domain (real), fsample=12000 Hz
+!Transform to time domain (real), fsample=12000 Hz
+     call four2a(cz,2*nfft2,1,1,-1)
      do i=0,nfft2-1
         j=nfft2-1-i
         iwave(2*i+1)=nint(real(cz(j)))