<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Apr 2, 2012, at 10:46 PM, Jean-Yves Avenard wrote:</div><blockquote type="cite"><div>You should lodge a bug to the ALSA folks. That ALSA reports that your<br>audio card supports 32 bits audio, when it doesn't...<br>Do so on either their bug tracker<br>(<a href="https://bugtrack.alsa-project.org/alsa-bug/login_page.php">https://bugtrack.alsa-project.org/alsa-bug/login_page.php</a>)<br>or via their mailing list<br></div></blockquote><div><br></div><div>Thanks again for your help.</div><div><br></div><div>My card has a CMI8768 chipset. After digging around a little, it appears it's intended that it supports a 32-bit sample size, for the purpose of allowing 24-bit samples. See for example this commit</div><div><br></div><div><a href="http://git390.marist.edu/cgi-bin/gitweb.cgi?p=linux-2.6.git;a=commitdiff;h=57bd68b8b18608cf2729f97fcb984b8521d19551">http://git390.marist.edu/cgi-bin/gitweb.cgi?p=linux-2.6.git;a=commitdiff;h=57bd68b8b18608cf2729f97fcb984b8521d19551</a></div><div><br></div><div>I went ahead and reported the bug with Alsa to point out the 32-bit samples produce silence after reproducing this with speaker-test.</div><div><br></div><div>Perhaps others might be interested; I found it's possible to work around this issue without recompiling MythTV by using alsa-lib's plug plugin. Adding an entry like such to /etc/asound.conf:</div><div><br></div><div><div>pcm.xyz {</div><div><span class="Apple-tab-span" style="white-space: pre; "> </span>type plug</div><div><span class="Apple-tab-span" style="white-space: pre; "> </span>slave {</div><div><span class="Apple-tab-span" style="white-space: pre; "> </span>pcm "hw:1,2"</div><div><span class="Apple-tab-span" style="white-space: pre; "> </span>format S16_LE</div><div><span class="Apple-tab-span" style="white-space: pre; "> </span>}</div><div>}</div><div><br></div><div>Defines a new device "xyz" to convert input to S16_LE, and passes it on. This seems to work as well.</div><div><br></div><div>-Steve</div></div></div><div><br></div></body></html>