As a session chair, how to familiarise oneself with the pronunciation of speakers' names?

When I am chairing a session, I always check a few minutes beforehand to ensure that all of the speakers are there. That's also a good time to check on pronunciation of names. Just say something like:

Can you please say your name for me? I'd like to pronounce it right when I introduce you.

Then it will be fresh in your mind, there'll be a decent chance of getting it right, and the speaker will know that you cared to consult them and try, even if you do end up screwing it up.

One possibility is to have a chat with the speakers over breakfast, if this is served at the conference place for all the participants. For example, a well-known conference in my field organizes the so-called speakers' breakfasts to allow a first contact between chairmen and speakers.

A second possibility is to check a few pronunciation guides on the internet (e.g. Inogolo): though not exhaustive (both in breadth and depth, because different pronunciations of the same name might not be adressed), they can sure be of help.

When a name comes from a non-English language, there's always the question whether the pronunciation has been anglicized or not. In such cases, I see no sound alternative to asking the speaker directly. For example, some of my siblings have anglicized the pronunciation of our common name "Blass" more than I have. I experienced another example a few years ago, when I chaired a session and had to introduce three or four speakers with non-English names. I knew that I had to check about the pronunciations, but I thought I had a clever idea: All the speakers had been either students or postdocs of a certain professor, whom I knew. So I just asked this professor about all the names. He said they all used the anglicized pronunciation. That struck me as unlikely on statistical grounds, so I stopped being clever and asked the speakers themselves. It turned out that all of them preferred the original non-anglicized pronunciations. (So much for my cleverness and my statistical intuition.)