On the Vu site you can find info and bootloader .... What do you need it for because specific to the duo4KSE does not exist but there is one for all 4K models
Install the file in the vuplus,due4kse folder on your decoder
and save it to a USB stick,
then update.
Done
Vu+ DUO 4K SE DVB-S2X FBC Twin Tuner PVR Linux Receiver UHD 2160p
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