ASIO4ALL is a very buggy driver setup, and I wouldn't suggest using it, but Organtechnology has it almost spot on.
Generally, yes, it's because you're connected to the wrong outputs, or the control panel is turned down, however you may also not have the outputs configured correctly in the software you're using. Select the Delta ASIO driver, yes, but don't forget to make sure you're selecting the correct output for your main outs.
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