You can’t tell by yourself. You have to provide the serial number code (14 digits under the barcode on the side of the box) to the FiiO support and they will check in their system and tell you. Revision is the same - 1.22

Got my K7 (from the new batch with the fixed 'sound drop' issue) last Monday and so far no problems at all. Turned off the RGB lights altogether using the provided tool and FW files from FiiO support.

@FiiO, are the upcoming devices from the new batch (with fixed issue(s)) visually identical to the old ones? If yes, how are we supposed to differentiate them from one another? Is there a specific serial number after which all devices are from the new batches?

Hello, Currently I have O2+ODAC (revB) (images attached), paired with Sennheiser HD650 (stock 6.5mm cable). I am exclusively listening to 24/96 flac vinyl rips or TR24 (if they are not compressed), through the USB port. As I am interested in the K7, I would like to find answers to the following...

Thank you all for the input.   I bought O2+ODAC yesternight at a discount. :)

  I can get the G5 for quite cheap. But if the price is not important, are the Schiit and ODAC technically better?

Hello,   Currently I have Yahama RX-V371 receiver and in 3 day I should get Sennheiser HD 650. Now, I know that the Yamaha is low budget piece of crap, so I am looking for alternatives.   I want to ask you whether Creative G5 is comparable in pure music audio quality to amp/dac combos like...

Thank you for your input! I will definitely check the sound that comes out of the Yamaha and will make a decision. I did check Schiit's products as well as Mayflower's O2+ODAC, but shipping outside US is not cheap...   I was thinking about considering also USB sound cards like Asus and...

Hello all,   In around 5 days I shall be proud owner of Senn HD 650 and now I am wondering whether the receiver I have (Yamaha RX-V371) will be good enough for the headphones...? If not, could you please recommend a headphone amp/dac in the range of 150-200€ ($160-210) which will make a big...