Hisense 55U8N / 55U8K tips and tricks.

First off, fun fact about these TVs, 55U8N is actually the exact same TV as 55U8K, down to the electronics and specs, so the firmwares are interchangable completely.  Thus the two listings for these TVs are mirrors of one another.

These TVs are considered Tier one support (the best), as R-T-B (the admin) personally owns and tests firmware on a 2024 Manufactured 55U8N.

Lets start by listing the firmwares in order of release, with a sort of changelog between versions from testing (Hisense does not provide this).  This should help you choose which firmware you want to flash.  Note on this TV, upgrading and downgrading both are seemingly possible and work well.

55U8K_55U8N_55E85GUA_N0918.zip - Version notes:

1.) This appears to be the earliest firmware I was able to find from users and a general internet search (maybe the first shipped with the original U8K?).  Anyhow, it works well and is mostly bug free but has a very old android build (July 2023).  I would not advise using this connected to the internet.  Maybe flash it and use it offline, or really firewall it off somehow.

FLASHING PROCESS: 

1.) see flashing1.txt.  To prevent automatic updates, either go offline or reference updates.txt.

55U8K_55U8N_55E85GUA_O0223.zip - Version notes:

1.) This appears to be the second released firmware I can find.  It's just a security update for GoogleTV as best I can tell, still pretty outdated though (GoogleTV security patch of late 2023), still really bug free in functionality.  If you want one to run offline or heavily firewalled for streaming with little to no bugs, this is your build.

FLASHING PROCESS: 

1.) see flashing1.txt.  To prevent automatic updates, either go offline or reference updates.txt.

55U8K_55U8N_55E85GUA_O0730.zip - Version notes:

1.) This build introduces a major UI overhaul (more sound options, picture pane improvements to visibility, a new support menu including TV details, etc), greater peak brightness to the panel (managable by the peak brightness setting, seems to top out somewhere between 1800-2200 Nits depending on model), and some nice EDID fixes for freesync premium in particular.  While that is kind of cool, this build unfortunately also comes with several bugs.  I will try to list them below in order of severity:

2.) BUG1:  All HDR picture modes other than HDR IMAX have completely wonky EOTF tracking, resulting in a very overly bright picture and impossible to calibrate HDR settings on a Desktop in windows.  You can work around this by forcing auto low latency to on, and then setting the profile to IMAX, but it's still a pretty major bug.  Somehow the IMAX HDR profile is immune, even in low latency game mode.  Note that you must set low latency game mode or Chroma 444 support is lost on the IMAX profile.

3.) BUG2:  During the captive setup process, a unknown error occurs, possibly some process crashing.  It does not seem to harm anything, but states "please try again" on the screen, somewhat disconcertingly.  It does not result in setup failing though.

4.) All in all, the bugs have work arounds and other than that this is a mostly stable build.  It's also based on AndroidTV Security patch from March 5th, 2024.  That's modern enough to let online freely, I feel.  It's what firmware R-T-B runs right now, as such.

FLASHING PROCESS: 

1.) see flashing1.txt.  To prevent automatic updates, either go offline or reference updates.txt.

55U8K_55U8N_55E85GUA_O1030.zip - Version notes:

1.) This build appears to be a bugfix / maybe a security update to O0730?  Whatever it is, it isn't worth running for most users as it has all the bugs of the above, plus these new fun guys:

2.) BUG3: The EOTF function in IMAX is now busted too, making everything overly bright.  You can compensate for this with a custom gamma curve, I guess, but...

3.) BUG4: Random horizontal artifacts/lines appear on the screen with no discernable pattern to them (they are random but highly irritating) in any resolution using high speed HDMI 2.1 FRL speeds (basically anything at or above 4k@120hz 10bpc).  Gsync or higher rates makes this worse.  Great work Hisense, right?  

4.)  In summary, I wouldn't flash this unless I was really worried about network security, and even then, the next build is probably a better choice.

FLASHING PROCESS: 

1.) see flashing1.txt.  To prevent automatic updates, either go offline or reference updates.txt.

55U8K_55U8N_55E85GUA_P0414.zip - Version notes:

1.) This version has all the bugs of the above, but is newer and probably has security improvements.  Also, it is packaged in a new OTA package format.  See below.

FLASHING PROCESS: 

1.) see flashing2.txt for this build, and probably anything newer.  To prevent automatic updates, either go offline or reference updates.txt.