Machine code debugging

[Aragorn]

Dear ddd'ers,

  I'm using ddd as an assembly-level debugger to peek around in programs
which only come in binary form...   When  stepi'ng  or  nexti'ng,  ddd's
machine  code  window  doesn't  always  reflect  the  program's  current
instruction pointer.  I mean: the ``green arrow'' doesn't update at each
stepi/nexti as it should...
  If I type ``x/i  $pc''  the  machine  code  window  recenters  itself,
pointing at the current $pc but if I make a macro (say: ``xi'')  out  of
the previous command and run this instead, the window _won't_  recenter,
even if gdb's output is exactly the same...

  What could be the matter?

  My gdb is: GNU gdb 5.0rh-5, the one which ships  with  Red  Hat  Linux
7.1...

thanks,
--
Aragorn