You must ensure that nothing will turn the power off to your DN-HD2500 whilst the firmware upgrade is taking place, so... dont try upgrading it whilst in a venue with a noise limiter fitted or when running from a generator, or on a car power invertor etc...

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Instructions:

(1) Copy the version up file (HD2500.bin) into a USB memory device. (Flash Drive, Jump Drive...etc)

(2) Turn the DN-HD2500 Power OFF

(3) Insert the Flash Drive, Jump Drive...etc to the side of the player marked USB-A

(4) Press and hold the two buttons marked, [SOURCE] button on Deck 1 and [BACK] button on Deck2 and then turn the power ON while holding down these two buttons. The version up screen appears, then release the two buttons.

(5) Press [CUE] button on Deck2.
The installed version number and the new version number appear in the display.

(6) Confirm the version number, then press [PLAY/PAUSE] button on Deck2.
Version up starts. (it takes about 15 seconds to complete).

(7) Keep power ON. Never shut the power off during version up.
If you shut the power off during this short wait period, the DN-HD2500 will require factory service, be careful!

(8) When the player is finished updating, Version UP complete! will be displayed.
It is now OK to Turn off the power to reset the machine back to normal mode.