It was read by John Lee, published in 2003. (I looked on the library catalog.) There’s an earlier recording (1991) by Patrick Tull.
I liked the reader on the discs I had ... pleasant voice, and the characters were reasonably distinct. However, I didn’t notice accents, especially, nor great dramatic flair. It could be the 1991 set that you were told about.
Yes it was Tull and no, he’s not Jethro’s brother. Seriously, I’ve heard he was the definitive voice for the O’Brian series.
Thanks for your insights.