acmStreamOpen() always fails!

[Oyl]

Tried to convert ADPCM / MP3 waves to standard PCM waves (to be able to use compressed waves in DirectSound<br>(IDirectSoundBuffer). btw, how can I fill those 2 pointers of sound data with ACM?). But even this simple example with source and destination format being standard PCM fails when opening the stream.<br>But &quot;ACMapp&quot; works just fine (with all formats). But I really don't know where my mistake is.<br><br>Sample code:<br><FONT FACE=monospace><br>// source format -- 44.1 Hz, 16 bit, mono<br>WAVEFORMATEX s;<br>s.cbSize = 0;<br>s.nAvgBytesPerSec = 88200;<br>s.nBlockAlign = 2;<br>s.nChannels = 2;<br>s.nSamplesPerSec = 44100;<br>s.wBitsPerSample = 16;<br>s.wFormatTag = WAVE_FORMAT_PCM;<br><br>// destination format<br>WAVEFORMATEX d;<br>d = s;<br>d.nChannels = 1; // not really needed<br><br>HACMSTREAM stream;<br>// always &quot;not possible&quot;! Why???<br>acmStreamOpen(&stream, NULL, &s, &d, NULL, 0, 0, ACM_STREAMOPENF_NONREALTIME);<br>// ...<br></font><br>HELP!<br>--Leo