Your issue is not firmware related (unless using Linux). You have flashed the drive and the info looks fine. What happens when you insert a UHD disc? If the disc does not even show in MakeMKV,B12ian wrote: ↑Wed Jan 21, 2026 5:00 amThat’s it-more power to it.nicholfd wrote: ↑Wed Jan 21, 2026 4:25 amI've never heard of country/source of the drive mattering for firmware.
What is the Mfg/model of the USB drive you purchased, as sold retail? What was on the box? Are you sure it was a BU40N drive internally?
Do you have 2 x USB or 1 x USB + 1 x power connections to the drive? 4K/UHD require more power than audio/DVD/Blu-Ray. Single USB ports/connections typically cannot supply enough power to a drive for 4K/UHD.
My friend has the 43888 and he said he could rip 4K with one usb cable.
I bought 43888, hoping it would Pioneer but I lost the lottery-BU40N.
Thanks for reminding me about the power supply.
I’ll try that tomorrow.
Thank you again
1. Clean the disc.
2. Always insert the disc and let the OS initialise it first before you open up MakeMKV.
If you are using Linux, it is recommended to use firmware BU40N 1.00.
Also, it is best to use USB ports direct from the motherboard, USB-C if possible or use an AC self-powered USB hub of at least 24w. Do not use case ports for optical drives as they often have poor quality wiring and may not provide enough constant power.
Now, if you get an error or the disc won't decrypt, copy and paste the log window text.
