anchor.diff:  (defconstant +mode-extension-1+ 1)
   (defconstant +mode-extension-2+ 2)
   (defconstant +mode-extension-3+ 3)
  +
   (defun get-mode-extension-string (channel-mode layer mode-extension)
     (if (not (= channel-mode +channel-mode-joint+))
         ""
  
positive.code: 
            (setf vbr (make-instance 'vbr-info))
            (let ((v (make-mem-stream (payload me))))
              (stream-seek v i :start)            ; seek to xing/info info
              (setf (tag vbr)   (stream-read-iso-string-with-len v 4))
              (setf (flags vbr) (stream-read-u32 v))
              (when (logand (flags vbr) +vbr-frames+)
                (setf (frames vbr) (stream-read-u32 v))
                (if (= 0 (frames vbr)) (warn-user "warning Xing/Info header flags has FRAMES set, but field is zero")))
              (when (logand (flags vbr) +vbr-bytes+)
                (setf (bytes vbr) (stream-read-u32 v))
                (if (= 0 (bytes vbr)) (warn-user "warning Xing/Info header flags has BYTES set, but field is zero")))
              (when (logand (flags vbr) +vbr-tocs+)
                (setf (tocs vbr) (stream-read-sequence v 100)))
              (when (logand (flags vbr) +vbr-scale+)
                (setf (scale vbr) (stream-read-u32 v)))
              (log-mpeg-frame "vbr-info = ~a" (vpprint vbr nil))))))))
  
  (defmethod vpprint ((me vbr-info) stream)
  
negative.code:                 (let ((hdr (make-instance 'frame :hdr-u32 hdr-u32 :pos pos)))
                    (if (load-frame hdr :instream in :read-payload t)
                        (progn
                          (check-vbr hdr (stream-filename in))
                          (log-mpeg-frame "Valid header being returned: ~a, searched ~:d times" hdr count)
                          (return-from find-first-sync hdr))
                        (progn
  