Under some circumstances, using ALSA due to bad rounding, some audio …

…samples would be lost.

Should the number of frames for period_size returned by ALSA be an odd-number, some samples would be lost.

Fix #9930.

Backports SHA:a56a759

mythtv/libs/libmyth/audiooutputalsa.cpp

@@ -725,7 +725,7 @@ int AudioOutputALSA::SetParameters(snd_pcm_t *handle, snd_pcm_format_t format,
 
     /* set member variables */
     soundcard_buffer_size = buffer_size * output_bytes_per_frame;
-    fragment_size = (period_size * output_bytes_per_frame) >> 1;
+    fragment_size = (period_size >> 1) * output_bytes_per_frame;
 
     /* get the current swparams */
     err = snd_pcm_sw_params_current(handle, swparams);