Mint 19.1 crashing

[noady]

Hi, I'm running a Dell Latitude 64 bit laptop.
I installed LM 19.1 recently.

everything was fine until multiple crashes;
Latest log message:
19:33:46 kernel: iwl3945 0000:0c:00.0: Can't stop Rx DMA.
19:33:46 kernel: iwl3945 0000:0c:00.0: Can't stop Rx DMA.
19:33:46 kernel: iwl3945 0000:0c:00.0: set power fail, ret = -5
19:33:46 kernel: iwl3945 0000:0c:00.0: Command C_POWER_TBL failed: FW Error
19:33:46 kernel: iwl3945 0000:0c:00.0: Error Reply type 0x00000000 cmd C_RXON (0x10) seq 0x0406 ser 0x017D0000
19:33:46 kernel: iwl3945 0000:0c:00.0: Read idx for DMA queue txq id (4), idx 5, is out of range [0-256] 4 4.
19:33:46 kernel: iwl3945 0000:0c:00.0: Read idx for DMA queue txq id (4), idx 4, is out of range [0-256] 4 4.
19:33:46 kernel: iwl3945 0000:0c:00.0: SYSASSERT (0x5) 0894062558 0x008B6 0x01E20 0x00320 0x00000 381

19:33:46 kernel: iwl3945 0000:0c:00.0: Desc Time asrtPC blink2 ilink1 nmiPC Line
19:33:46 kernel: iwl3945 0000:0c:00.0: Status: 0x000302E4, count: 1
19:33:46 kernel: iwl3945 0000:0c:00.0: Start IWL Error Log Dump:
19:33:46 kernel: iwl3945 0000:0c:00.0: Loaded firmware version: 15.32.2.9
19:33:46 kernel: iwl3945 0000:0c:00.0: Microcode SW error detected. Restarting 0x82000008.
19:31:09 systemd: Failed to start flatpak-org.libreoffice.LibreOffice-6839.scope.
19:31:01 sudo: brian : a password is required ; TTY=pts/0 ; PWD=/home/brian ; USER=root ; COMMAND=/usr/sbin/hddtemp -nq -u C /dev/sdc
19:11:12 kernel: iwl3945 0000:0c:00.0: Can't stop Rx DMA.
18:51:07 kernel: usb 6-1-port1: disabled by hub (EMI?), re-enabling...
16:29:38 kernel: iwl3945 0000:0c:00.0: Can't stop Rx DMA.
08:43:04 pulseaudio: [pulseaudio] bluez5-util.c: GetManagedObjects() failed: org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
08:42:21 lightdm: PAM adding faulty module: pam_kwallet5.so
08:41:44 wpa_supplicant: dbus: Failed to construct signal
08:41:33 kernel: Error calling EVIOCSKEYCODE on device node '/dev/input/event9' (scan code 0x100150, key code 190): Invalid argument
08:41:30 kernel: leds dell::kbd_backlight: Setting an LED's brightness failed (-5)
08:41:09 kernel: [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [PLANE:28:plane A] flip_done timed out
08:41:09 kernel: [drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:34:pipe A] flip_done timed out
08:41:09 kernel: [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [PLANE:28:plane A] flip_done timed out
08:41:09 kernel: [drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:34:pipe A] flip_done timed out
08:41:09 kernel: sd 4:0:0:0: [sdb] Assuming drive cache: write through

Any help be great.
I have Timeshift saved on a stick (continuous) but would like to resove this properly

[Lord Boltar]

The iwl3945 is your Intel Wireless is not shutting down or Mint is not able to turn it off during shutdown - can you manually turn off the wireless first before going to shutdown and see if your errors change - also check to make sure your kernel is up to date

[noady]

Thanks for that, but...
Looked at the crash log and found a critical error:
""CRITICAL: t+94.77482s: We failed but the fail whale is dead sorry...""
I've double-punctuated this message in case this is a hack i have been subject to.
Have ditched Mint 19.1 64bit and am back on 32Bit Serena.
I reckon I should notify the police about this.
Thanks, Brian

and, yeah, Kernel was up to date (yesterday)
AND the critical error message had a comma between the "dead" and the "sorry" words
which made me suspect this could be a hack.

[Lord Boltar]

In this case the "fail whale" is an error message logged by GNOME if something went wrong. It's named after a illustration by Yiying Lu used by Twitter to display errors.
If it is dead it means that there's not enough of GNOME running to display the error.

[smurphos]

Which Desktop environment were you running?

Out of interest is your boot time really slow?