Sorry for the delayed responses, I've been busy with work. dmesg shows some EAC errors between removing and adding the external drive.

"EAC mode: play enabled, rec enabled
EAC mode: play disabled, rec disabled"

there is a number of these, the last one being an enabled line. There are numbers to the left of these lines, xxx.xxxxxx Looks to be progressive for all of dmesg, if it's relevant, let me know and i'll post them.