Having recently installed Lubuntu 18.04, I wanted to burn an audio CD using the k3b software. Only by launching engraving, I came across this error:

cdrecord has no permission to open the device 
You may use K3bbsetup to solve this problem.

The solution is quite simple, the user accessing the CD / DVD drive must be in the group ‘cdrom’, so to enter the following command in a terminal:

sudo chown root:cdrom /usr/bin/wodim

Wodim being the new name of ‘cdrecord’. However, in order for this change to work, I was then forced to run k3b as root:

sudo k3b

I was also faced with a strangely similar problem with the brazier software, I did not test if after that This modification worked, but I think the cause was the same.