WordPress Database Table Crashes

I'm running into a consistent problem with one of my client's sites where some database tables crash. Usually at least once a week this happens.

I go in to phpMyAdmin and repair the affected tables and all is well again. But I'm trying to figure out what might be causing the issues.

Could it be that there is something wrong with my hosting provider's database server, where WordPress is trying to make a write to the DB and the server goes down in the middle of it?

The last crash happened a few minutes ago. I tried to use WordPress to repair the tables but this is the message I received:

transit_posts: Size of indexfile is: 363483 Should be: 119808
transit_options: Table is marked as crashed
transit_term_taxonomy: Size of indexfile is: 6528 Should be: 4096

Anyone have ideas as to what could be leading this to crash so often?