ReadyNAS Pro rebooting and resyncing, with file copy hangups and other issues

The exact model number for the Seagate IronWolf 4TB drives is ST4000VN008-2DR166.   I previously stated ST4000VNB08.

Here is the SMART info for each.  Note the Power On Hours, Head Flying Hours, Total LBAs Written, and Total LBAs Read.   As you can see, those can't possibly be accurate since these are new drives and I would need to be extremely old to put that many hours on them, Ha Ha!

SMART Information for Disk 2

Model: ST4000VN008-2DR166
Serial: 
Firmware: SC60
SMART Attribute
Spin Up Time 0
Start Stop Count 45
Reallocated Sector Count 0
Power On Hours 34308198760564
Spin Retry Count 0
Power Cycle Count 29
End-to-End Error 0
Reported Uncorrect 0
Command Timeout 0
High Fly Writes 0
Airflow Temperature Cel 31
G-Sense Error Rate 0
Power-Off Retract Count 10
Load Cycle Count 45
Temperature Celsius 31
Current Pending Sector 0
Offline Uncorrectable 0
UDMA CRC Error Count 0
Head Flying Hours 42069204664398
Total LBAs Written 3925796440
Total LBAs Read 17674520602
ATA Error Count 0

SMART Information for Disk 6

Model: ST4000VN008-2DR166
Serial: 
Firmware: SC60
SMART Attribute
Spin Up Time 0
Start Stop Count 38
Reallocated Sector Count 0
Power On Hours 182445915766869
Spin Retry Count 0
Power Cycle Count 28
End-to-End Error 0
Reported Uncorrect 0
Command Timeout 0
High Fly Writes 0
Airflow Temperature Cel 31
G-Sense Error Rate 0
Power-Off Retract Count 11
Load Cycle Count 38
Temperature Celsius 31
Current Pending Sector 0
Offline Uncorrectable 0
UDMA CRC Error Count 0
Head Flying Hours 215585883422785
Total LBAs Written 3925488218
Total LBAs Read 13777168712
ATA Error Count 0

The Frontview disk table:

Disk 1 Seagate ST32000644NS 1863 GB , 37 C / 98 F , Write-cache ON  OK
Disk 2 Seagate ST4000VN008-2DR166 3726 GB , 32 C / 89 F , Write-cache ON  OK
Disk 3 Seagate ST2000VN000-1HJ164 1863 GB , 32 C / 89 F , Write-cache ON  OK
Disk 4 Seagate ST2000NM0011 1863 GB , 37 C / 98 F , Write-cache ON  OK
Disk 5 SAMSUNG HD204UI 1863 GB , 33 C / 91 F , Write-cache ON  OK
Disk 6 Seagate ST4000VN008-2DR166 3726 GB , 32 C / 89 F , Write-cache ON  OK
Fan SYS 932 RPM OK
Fan CPU 2109 RPM OK
Temp SYS 58 C / 136 F [Normal 0-65 C / 32-149 F] OK
Temp CPU 20.5 C / 68 F [Normal 0-60 C / 32-140 F] OK