The documentation for Channel::setPosition states;
If playing a Sound created with System::createStream or FMOD_CREATESTREAM changing the position may cause a slow reflush operation while the file seek and decode occurs. You can avoid this by creating the stream with FMOD_NONBLOCKING. This will cause the stream to go into FMOD_OPENSTATE_SETPOSITION state Sound::getOpenState and Sound commands will return FMOD_ERR_NOTREADY. Channel::getPosition will also not update until this non-blocking set position operation has completed.
Which functions will return FMOD_ERR_NOTREADY when the sound is in FMOD_OPENSTATE_SETPOSITION?
What is the definition of a “Sound command”?