From 6f79b8be8f7edb8cc6f18b6a12ede2858d65b681 Mon Sep 17 00:00:00 2001
From: Tom Rondeau
Date: Tue, 2 Aug 2011 20:46:50 -0400
Subject: patch: applying Alexandru Csete's patch (that I though I already
 applied...)

---
 gr-audio/lib/alsa/audio_alsa_source.cc | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/gr-audio/lib/alsa/audio_alsa_source.cc b/gr-audio/lib/alsa/audio_alsa_source.cc
index 4f0042b22..2f4506f71 100644
--- a/gr-audio/lib/alsa/audio_alsa_source.cc
+++ b/gr-audio/lib/alsa/audio_alsa_source.cc
@@ -217,8 +217,14 @@ audio_alsa_source::check_topology (int ninputs, int noutputs)
   unsigned int nchan = noutputs;
   int err;
 
-  // FIXME check_topology may be called more than once.
+  // Check the state of the stream
   // Ensure that the pcm is in a state where we can still mess with the hw_params
+  snd_pcm_state_t state;
+  state=snd_pcm_state(d_pcm_handle);
+  if ( state== SND_PCM_STATE_RUNNING)
+    return true;  // If stream is running, don't change any parameters
+  else if(state == SND_PCM_STATE_XRUN )
+    snd_pcm_prepare ( d_pcm_handle ); // Prepare stream on underrun, and we can set parameters;
 
   bool special_case = nchan == 1 && d_special_case_stereo_to_mono;
   if (special_case)
-- 
cgit