playDSP plays only monophonic?

I have a custom DSP that I play with playDSP that is fed by a custom wave reader from a 16 bit stereo file. For some reason it is always playing it mono, means I hear the same sound on the left and right side and not as expected a stereo experience. Does anyone have an idea why this happened?

In FmodEx there was the channels option that is now entirely gone.

old FMODEx code:

memset( &dsp_desc, 0x0, sizeof(dsp_desc) );
dsp_desc.channels = 2;
strncpy(, "Player", 32);
dsp_desc.version = 1; = &DSPReadCallback;

You may be looking for DSP::setChannelFormat, which lets you set both the number of channels the DSP will receive with numchannels, as well as the mapping of those channels (i.e. Stereo) with source_speakermode.

Hope that helps!