Known Issues in Whonix
"apt source package" will show "dpkg-source: warning: failed to verify signature"
This is not a security issue, but only a warning. Read the entire thread here for more information.
This warning message can be removed with the following workaround below.
sudo unlink /etc/dpkg/origins/default sudo ln -s /etc/dpkg/origins/debian /etc/dpkg/origins/default
2. Download the source package.
apt source package
3. Undo afterwards to prevent unexpected issues.
sudo unlink /etc/dpkg/origins/default sudo ln -s /etc/dpkg/origins/whonix /etc/dpkg/origins/default
Proxychains Tor Browser Issue
Using Tor Browser in conjunction with proxychains for the connection scheme:
does not currently work. For more information, see here.
See also VirtualBox/Troubleshooting
If you see the following error and freezing.
433.348893] mptscsih: ioc0: attempting target reset! (sc=ffff81021b950940) 433.348896] sd 0:0:0:0: [sda] CDB: ATA command pass through(16): 85 08 0e 00 d5 00 01 00 09 00 4f 00 c2 00 b0 00 433.605026] mptscsih: ioc0: target reset: SUCCESS (sc=ffff81021b950940
It has been reported that running from an internal HDD/SSD works better than running from external devices.
One workaround might be avoiding high load on your host operating system. If this bug causes a lot of problems, then your only option is to switch to another platform.
Mounting (CD / DVD) Devices
If the device auto mounter is broken, see if
Start menu →
System Settings →
Removable Media helps.
The following workaround can be used.
sudo mkdir /mnt/cdrom sudo mount -o ro /dev/cdrom /mnt/cdrom/
Using the ro flag will mount the CD / DVD in read-only mode. If a CD / DVD is not being mounted, then drop the "-o ro" parameter.
Help fixing this bug is welcome! (ticket)
Network Manager Systray Unmanaged Devices
Short answer: Unmanaged devices are unrelated to Whonix functioning and should not concern the user.
Long answer: 
Suspend / Hibernate Issues
Short: Avoid suspending or hilbernating the computer or Whonix VMs while Whonix is running.
VLC / Video Player Crash
The following workaround can be used; this is the default in recent builds (like Whonix 14). 
- Whonix does not use network manager to manage either eth0 or eth1.
- In Non-Qubes-Whonix, networking is managed by ifupdown.
- Qubes-Whonix uses a custom /lib/systemd/system/qubes-whonix-network.service and is unaffected by this issue.
To reduce confusion, the ideal Whonix default would either: prevent the systray item starting, hide the systray item, or suppress the information being presented. Network manager is installed so users can easily setup VPNs with its intuitive graphical user interface.
All attempts to fix this long-standing issue have failed. Help is welcome to fix it.
Fix Unmanaged Devices Network Manager