Nice write up! Good for you J1 users 
Would be good to make it a wiki, if you want to.
Thanks Mechanikus. Appreciate the advice. The only issue I seem to have is with the right extruder throwing a filament load error quite frequently. I followed the advice others have posted and tightened the grub screw on the gear (it was a bit loose), but the problem still hasn’t resolved. Not sure if the grip on the filament on the right is weaker than on the left. Any advice?
Apart from the things mentioned above (what you explain might be something related to clogging): not yet, sorry - as noted above, I am still waiting for my own J1 and only collect and share anything that might be helpful to get the machine up and running as smooth as possible.
Please be so kind as to refer to any threads about your problem in the forum or create a new one - this thread is really just intended to provide an overview.
Appreciate your quick response Mechanikus. Apart from the grub screw being loose, I took the side plates off the nozzles to see if there was anything else causing the problem. All else looked good, so I thought I would try another print, this time changing slicer settings.
I reduced the retraction distance to 2mm (down from 6.5mm default) and found this made little difference. I have found however that reducing the retraction rate from 40mm/s to 25mm/s seems to have fixed the issue. This is for PLA and PLA+. For some weird reason, only the RHS nozzle seems to have this issue. I have managed to get 2 successful prints in copy mode without any feeder issues now 
German:
Hallo zusammen,
ich habe hier noch einmal etwas zusammengestellt, um unbeabsichtigte Geräusche zu beseitigen, die vom Gehäusedeckel und der Rückwand kommen.
Auf der Oberseite des Rahmens habe ich Tesa Gewebeband an den neuralgischen Stellen aufgeklebt.
Somit ist das Klappern des Deckels schon einmal beseitigt.
Zusätzlich, mit dem Tesa, habe ich die Fläche beklebt, auf der die Filament Führung aufliegt, womit sich lästige Schleifgeräusche abstellen lassen.
Und zum Schluss, habe ich mittig oben und unten der Rückwand, dünnen Schaumstoff (2 mm) eingeklemmt, denn auch hier klappert es bei sehr schnellen Bewegungen.
Zusätzlich habe ich noch eine Gehäuseentlüftung eingebaut, somit kann der Druckerdeckel drauf bleiben, egal mit welchen Filament gerade druckt.
Englisch:
Hello, everyone,
I’ve put something together here once again to eliminate unintentional noises coming from the case top and back panel.
I glued Tesa fabric tape to the neuralgic spots on the top of the frame.
This eliminates the rattling of the lid.
In addition, I taped the Tesa to the surface on which the filament guide rests, which eliminates annoying grinding noises.
And finally, I clamped thin foam (2 mm) in the middle above and below the back wall, because it rattles here too with very fast movements.
In addition, I have installed a housing ventilation, so the printer cover can stay on, no matter which filament is currently printing.
Many thanks to @Mechanikus and @i3sven for sharing their thoughts & solutions.
I´m waiting for my J1 and assume to get in march … and it´s great to read about the things that you’d rather pay attention to right away
@xchrisd: I cannot seem to edit the first post any more. Could you add three more things to the list I noticed on my printer? If you want, make it a Wiki entry and link to it here.
Made it to a wiki for you, please edit it yourself .
Great, thanks
have the same problem, but with both extruders. I have reported the problem to the service department.
Did your fan blow the Air Inside to the Printer or other ways?
Think my silent ones are not powerfull enough to blow the hot air from inside to outside
Hi John,
maybe I can help you too? I have now also installed an extension above (+70mm). Now the Bowden tubes finally go free 
In the rear panel I have installed 2 x 50mm fans with a Temp/PWM control.
These BLOW the air to the OUTSIDE. This is the same at my old full housed GermanRepRap.
Today I finished my stuff and measured the temperature with the lid on - it’s almost the same Temp-Level as without the lid. That work well and till now i did not tune the controler.
In addition, it seems logical to blow out the warm air. To “pull out” the warm air is better because there would be more back pressure the other way.
Maybe i post more of that later on.
Got the same done. Got extension and 2x 60 fans on the back with Temp Sensors, but that’s not my problem. My problem are clogging, rattling heads and damaged rails.
But thanks for the pics, look pretty well the extensions. Maybe you can make some for 60x10 fans. Nice design
I got mine in a duct on the filament holders, my spools are on a wall mount
And I put some cooling Aluminum blocks on the Motors, that helps too
Next days I make heatsink paste on the heads, upgrade the gears and put other Nozzles on it, change heatsink too. I work on a better filament guide for the extruder heads, some filaments are unable to print with that angle on the heads and the rotation of the guide is not good for the filament I’ve seen.
Can you please share your riser design? I think - besides me 
- there might be others interested in building it.
Yeah, awesome Design. That’s a good idea. I was use the filament holders on the back for some 60x10 fans.
That Riser with fans are pretty 
I agree. That looks pretty nice. I think It would be great to combine your design with a ptc heater + thermostat and use it to push heated air in.
Hi there,
now i uploaded the STL files to thingiverse
the additional parts i used are
2x 50mm silent fan
PWM controller board with temp sensor
DC Power Jack Socket 5,5 X 2,1 mm
and a 12V power AS/DC adapter
4x washers Ø15mm at cornes bottom
4x Ø15mm x 3mm Neody magnets at the corners upper side
Du hast das echt genial, hinbekommen. Könntest du mir die step datei hochladen? Dann könnte ich, wenn du nichts dagegen hast, es für meine Zwecke anpassen.
Parametrisch in FreeCAD, dann kann man Höhe, Lüftung etc. nach Gusto anpassen. Würde ich übernehmen, obwohl mein J1 noch gar nicht da ist
A parametric design in FreeCAD would be good to let one adjust the height and vent openings suiting your tastes. I would volunteer - though my J1 has not arrived yet.