[Xenon]

// ****** PERSISTENT CONNECTIONS ******
// This option allows you to turn persistent connections to MySQL on or off.
// The difference in performance is negligible for all but the largest boards.
// If you are unsure what this should be, leave it off.
// 0 = Off; 1 = On
$usepconnect = 1;

try to change that value from 1 to 0, or vice versa, depending on actual status

i cannot say for sure if that'll help, but i know it has helped some users in the past