I have Sony NW-A55HN and I always use their DAC via Bluetooth. I don't need the MP3 / ACC Player, just the DAC. Can you recommend a DAC better that NW-A55HN for around 100-300 USD? Creative Sound Blaster X1 has better DAC than Sony NW-A55NG?

How is the battery drain with the Mr. Walkman firmware? Any contraindications?

I have a friend that have Sony NW-A55 with Sony IER-NW500N headphone, I have test it and the sound looks great! Someone can recommend me some headphone cheap but with the same sound quality. I have a 50-150 USD budget.

Thanks for your reply. So the quality of sound using DAC PC USB or Bluetooth receiver is the same?

When I use Bluetooth from a PC to SONY NW-A55 with Sony's bluetooth receiver, Is a55 using the DAC or just when I connect via PC USB cable?