The 'yes' man

I wouldn't say Coventry is a very strong accent, but of course any unfamiliar accent can be difficult to understand. It's also possible he just isn't a very clear speaker. If it's a conference call - is it a problem with his phone?

Does anyone else have this problem? Perhaps your boss needs to speak to someone at their end for some training for this guy on dealing with non-native speakers.

Otherwise, you'll just have to hope you improve with practise.

Will there be any point at which you meet the Coventry guy in person? I think if you spent some reasonable amount of face-to-face time with him you would probably adjust to his accent fairly quickly. If it's just a few minutes on the telephone once a week I think it's going to be difficult.

Some people have a grasp of how to speak to non-native speakers and some people simply don't.

Sorry I can't be of more help. Maybe others will have more useful ideas.

Coventry speakers have what I'd usually describe as a Birmingham accent, also known (by its speakers) as Brummie. This link says more about it:
http://www.bbc.co.uk/dna/h2g2/A496352

Although we (in the south of england) make jokes about Brummies, the accent is not hard to understand, even for foreigners learning English. I do not believe a brummie accent can explain why your colleague is so hard to understand.

It will be partly the accent and partly the guy having no idea how to make himself more understandable to a non-native speaker (or not caring to do so, perhaps for various male-ego-related reasons).

I do not believe a brummie accent can explain why your colleague is so hard to understand.

Locals from Birmingham were being interviewed on the news a couple of nights ago regarding the takeover of Cadbury by Kraft. One of the men had a very strong accent that I had to really listen to to understand. I have to say, conference calls can be a pain, especially when people are on speakerphone, speaking quietly and/or mumbling.

Although we (in the south of england) make jokes about Brummies, the accent is not hard to understand, even for foreigners learning English.

I'm not so sure about that. As an American, I wouldn't quite say Brummie is "hard for me to understand," but I would also certainly not say that it is "easy," and I can well imagine some non-natives would find it as impenetrable as a Texas drawl or a Scottish burr.

The OP might try searching the Internet for sound files of speakers from the West Midlands to practice. He could start here.

Thanks for that link, zashibis! Perhaps simpletraveller could look for a recording that sounds like the conference call presenter. I don't imagine that he's harder to understand than this old codger.

Oy think the link at throi ova emphasoises the rolled R thing but utherwoise is pretty akurat.

Thank the Lord for small mercies and that tonya001 isn't a Brummoi.

I work in Coventry. The accent really is quite distinct from Birmingham/Brummie, despite the short distance, and as other posters have said, is not that different from the'standard' south-eastern accents that foreign learners are likely to be exposed to.
Of course it is possible that this individual has grown up elsewhere than Coventry, but otherwise I imagine it is a case of his personal speech style. I sympathise, having spent much of the last decade in audio and video meetings with French colleagues, and it can be hard going in a large meeting where you are not involved constantly and can't see the person face to face.