c# - Very strange MySQL timeouts occurring on just one developer machine -

i'm not optimistic getting answer one, since it's such weird , seemingly machine-specific issue, i'm posting in hopes else has figured 1 out.

i'm developing application in c# using visual studio , mysql.data ado.net driver (version 6.9.8) database access. twice, i've run situation simple sql queries worked moments before start timing out. point forward, never succeed again -- on machine. every other query in application (and there hundreds) works fine, 1 query, if change slightly, never works again. if push code , developer runs it, code works on machine.

as example of how simple these queries are, here's 1 i'm having issues with:

select * user_preferences (user_id=@user_id) limit 1 

the table i'm selecting has 1 row , 4 columns. couldn't simpler. while query waiting time out, not appear in process list mysql, have assume either never made server or server returned instantly , mysql connector failing return response. i'd figure out which, doubt make difference either way.

so summarize, query worked fine morning. changed nothing except unrelated code, , briefly started returning no data. started debugging it, , times out. developer runs code, , works perfectly.

i'm @ complete loss, here. short of figuring out, fear i'm going have re-image laptop, , i'd avoid if @ possible. appreciated, though said, it's quite shot in dark.

edit: c# code in question:

using (var connection = new mysqlconnection(connectionsettings.getconnectionstring()))                 {                     await connection.openasync(cancellationtoken);                     using (var reader = await mysqlhelper.executereaderasync(connection, sql.query.tostring(), cancellationtoken, sql.parameters.toarray()))                     {                         while (await reader.readasync(cancellationtoken))                         {                             readeraction(reader);                         }                     }                 }