[cups] looking for clues in a brother MFC-J6920DW install thats not working correctly

[Gene Heskett]

Greetings;

This install is on debian wheezy, with cups 1.5.3, using the brother 
supplied drivers.

htttp://localhost:631/printers/MDCJ6920DW/printers/set default options, 
has a section called advanced color which gives 5 options
a brightness trim of -19 to +19
a contrast   trim ''  '' ''  ''
a red        trim ''  '' ''  ''
a green       ''  ''  '' ''  ''
a blue        ''  ''  '' ''  ''
There is also a color enhancement on/off on that screen, and a 3 position 
switch on the adjacent screen to the left for none-natural-vivid.
With vivid, the test page is very pastel, and the grey scale bar has a 
white band about 1/16" wide at what should be the black end of that 
scale. The only setting there that seems to have any effect is none, 
where it might be using 5% more ink,

None of the options on the advanced color screen have any effect, as if 
its in the extreme ink saver mode.  And it is, an ink tank lasts several 
reams of paper.
Looking in /var/spool/cups, at the cxxxx files. none of the advanced 
color settings are getting to those files, so in /var/log/cups/error_log 
I see 18 lines from the experiments just now, that report this:

W [19/Oct/2018:11:14:51 -0400] failed to CreateProfile: 
org.freedesktop.ColorManager.AlreadyExists:profile 
id 'MFCJ6920DW-Gray..' already exists

W [19/Oct/2018:11:14:51 -0400] failed to CreateProfile: 
org.freedesktop.ColorManager.AlreadyExists:profile id 'MFCJ6920DW-RGB..' 
already exists

W [19/Oct/2018:11:14:51 -0400] failed to CreateDevice: 
org.freedesktop.ColorManager.AlreadyExists:device id 'cups-MFCJ6920DW' 
already exists

Is this something I can fix by diddling perms and such? Heck, I don't 
even know where those "profiles" live, they are not something I have 
tripped over yet. Reading /etc/cups/cups-files it says nothing should 
resolve to user 0 for security reasons, yet the only file in that 
directory that is not owned by root is the brprinter-install file which 
I own as 1st user.

What can I do to straighten out this mess?

Too much info argues with itself.

Many thanks for help.

-- 
Cheers, Gene Heskett
--
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Genes Web page <http://geneslinuxbox.net:6309/gene>