Fixed for bug 2845. This is a bit of a quick-n-dirty patch.

The assertion looks for extremely small generated values and crash if
found one.
Removing the assertions seems to cause no arm and audio files of various
format play fines.
Moreover the problem seems to have completely disappered in recent
Debian distros, for example it was reproducable in Stretch but no more in
Buster.

Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
(cherry picked from commit 5d9981995e)

flow/gsl/gslwaveosc.c

@@ -219,7 +219,6 @@ gsl_wave_osc_process (GslWaveOscData *wosc,
 	}
     }
   g_assert (!GSL_DOUBLE_IS_NANINF (wosc->y[0]));
-  g_assert (!GSL_DOUBLE_IS_SUBNORMAL (wosc->y[0]));
 
   wosc->done = (wosc->block.is_silent &&   /* FIXME, let filter state run out? */
 		((wosc->block.play_dir < 0 && wosc->block.offset < 0) ||