As far as i can judge the logs and talking about own experience, i'd say return the unit to reseller and ask for other one. Ofcourse Sidehack should be able to give you a more clear view on the logs.
Did you check this:
1] Try another PSU, did you check PSU type?
2] Are you using GS breakoutboard? (in my experience it works the best)
3] Did you check USB cable, try using good quality
4] Did you use good cabeling to power the R606? (make sure youre cabling is right, i once got cabeling not made right. On some points black and yellow where switched).
5] ambient temperature, is it not to high?
6] are youre poolsettings OK, no typo or what so ever?
7] did you try another pool? (once i had problems with R606, on other pool no problems at all).
8] did you try to use them without asic+? Meaning the use of
--noboost or
--lowboost option
9] did you try lower speed?
10] try combinations of 7 to 9.
11] are you using the USB 2 ports on the pi4?
If i read the source of cgminer, starting @line 1978, it does indeed reset like this and perform a hotplug, so that is normal behaviour:
1: GSI 1 - forcing usb_nodev()
[2021-01-01 12:47:58.088] GSI 1 failure, disabling!
[2021-01-01 12:47:58.088] 1: GSI 1 - shutting down
[2021-01-01 12:47:58.190] 0: GSI 0 - Toggling ASIC nRST to reset
[2021-01-01 12:47:58.454] 2: GSI 2 - init_count 11
[2021-01-01 12:47:58.454] Hotplug: GekkoScience added GSI 2
Maybe, there is an USB issue @ the pi, or when it is on more than 1 pi, it could be cabling.
Somehow one of my pi4 USB-ports is not working well with R606, the other one is working without any problem, of course USB2 ports.
Hope this helps a bit.
I am using HP DPS1200-FB with breakout from eBay. This setup has worked with other miners (Antminer, Futurebit Apollo, etc.) without issues. I have swapped a number of USB cables and PCI-E cables so no issue here. Ambient temp is around 20 deg and pool setting is definitely correct. Unfortunately I did not try without asic+ or lower speeds, but I did try it on a Pi 3, Pi 4 (both USB 2 and 3 ports) and laptop running Win10 and all yield the same result.
Luckily I was able to return unit to reseller, and have more on the way so hoping those will be problem free!