Ender-3 randomly pausing since Marlin upgrade

What is the problem?

Upgraded the factory firmware on my Ender-3 to Marlin
now, it has started randomly pausing during printing for 1/2 to 2 seconds then continuing on. does it even on simple prints (20mm calibration cube) No error messages in the serial.log, no other errors I am seeing.

What did you already try to solve it?

Found a post where someone resolved it by upping the baud rate in the marling configs. recompiled Marlin for 250000 baud. no change
Replaced USB cable with a short brand new cable, High quality, EMI suppressed etc. No change. Took the octopi from my Anet printer and hooked it to the ender, and it does the same thing. Pi's are Both Pi4B's this wasn't doing it before Marlin.
Printing the same gcode from the SD card and it isn't doing the random pauses.
I am seeing a lot of the following :

2021-09-05 16:47:24,317 - Send: N1352 G1 X108.7240 Y121.4520 E5.1183*96
2021-09-05 16:47:24,337 - Recv: ok
2021-09-05 16:47:24,339 - Send: N1353 G92 E0.0000*93
2021-09-05 16:47:24,396 - Recv: X:108.72 Y:121.45 Z:3.80 E:0.00 Count X:9479 Y:9713 Z:1550
2021-09-05 16:47:24,398 - Recv: ok
2021-09-05 16:47:24,400 - Send: N1354 G1 E-1.0 F2100*25
2021-09-05 16:47:24,460 - Recv: ok
2021-09-05 16:47:24,462 - Send: N1355 G1 Z4.000 F1200*47
2021-09-05 16:47:24,494 - Recv: ok
2021-09-05 16:47:24,496 - Send: N1356 G1 X104.2000 Y121.8000 F6000*117
2021-09-05 16:47:24,570 - Recv: ok
2021-09-05 16:47:24,572 - Send: N1357 G1 E0 F2100*40
2021-09-05 16:47:24,653 - Recv: ok
2021-09-05 16:47:24,656 - Send: N1358 G92 E0.0000*86
2021-09-05 16:47:24,666 - Recv: X:104.20 Y:121.80 Z:4.00 E:0.00 Count X:9284 Y:9715 Z:1550
2021-09-05 16:47:24,667 - Recv: ok

Have you tried running in safe mode?

yes No change

Did running in safe mode solve the problem?


Systeminfo Bundle

You can download this in OctoPrint's System Information dialog ... no bundle, no support!)

bundle attached
octoprint-systeminfo-20210905172739.zip (123.3 KB)

Additional information about your setup

OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible


Upgrading to Marlin 1.1.9 - why not the 2.0.x versions? It sounds quite like this 'new' firmware you've installed is causing the problems. Can you go back the manufacturer's version to test it?

According to Creality's site, is the latest I can run on the old V1 8 bit main board. Not sure if that is due to limited memory size or what, they weren't specific. Unfortunately, I've been trying to find a way to go back to the old 1.1.6 creality firmware, but I can't find any info on how to reload the .hex file. Last night I ordered their 4.2.7 silent main board.

That may be the latest version that Creality offers, but you can certainly run Marlin 2.0.x on the 8bit boards. I did back when I still had a 1.1.4 board in my Ender 3. The only real limitation is the small amount of flash storage those boards offer.