That is totally not true if you look at these measurements.
Flat down to 20 Hz! Thank god! (otherwise it would be a faulty device)
Sorry i didnt mean to say it cant put out low/deep bass period.. But that it just isnt going to be satisfactory to anyone who loves sub bass. 2 other people agree with me. So there are 3 of us who feel like this DAP is unusual in that regard.