Hi,      Thanks for the English instruction, it finally work. Apparently, I need to select the driver from amd64 folder, kind of strange as my notebook is Intel i5 running W7 64bits. After driver installed, firmware upgraded smoothly.    Currently trying to run-in the N1 with the PAA-1 Pro...

Hi YOT,        To update the firmware, I am having trouble getting the hisound.sys driver install in Windows 7 64bits OS. Are you using the same environment ?     thanks.

    Well, probably thinking of a higher end portable audio player like maybe the HiSoundAudio Studio V or others, but not sure whether it's bang for the buck to upgrade. I did explore the desktop option, but the investment will be quite significant.

Can help to suggest a better source than RocooP when matching with K550 ? So far I don't notice any hissing sound from this combination. I am currently exploring other source to get the maximum performance out of K550, some suggestion here would be great, thanks in advance.

Quote: I am excited, better sound quality then RocooP, amazing. Looking forward receiving the Nova, hopefully it will work well pairing with AKG K550 combination.

     Glad it has a SD slot. I like the slim design, fit inside pocket nicely. Hopefully the battery can last and sound quality comparable to RocooP.

Just bought my can yesterday evening. Below is my experience to share after listening for 3 hours. I am not an audiophile expert, try to describe as best I can.   My K550 is powered by Rocoo P DAP. when listening at home(pretty quiet, except the floor stand fan noise), volume set to 15 is...