After initial Tropo configuration, get a fatal maximum function nesting when trying to edit

I did a clean install of VoIP Drupal on my development box, made sure all the dependencies were met and started setting up to use Tropo. I was able to enter in all the information including tokens and default voices.

I realized that I needed to change some of the configuration options, and went to

http://my.site/drupal7site/?q=admin/voip/servers/tropo

and get

Fatal error: Maximum function nesting level of '100' reached, aborting! in /var/www/lcfcadmin/includes/database/database.inc on line 2115

Default voice is Simon. Here's the last few lines of the error message

85 0.6440 21462128 VoipVoice::getVoice( ) ../voipvoice.inc:64
86 0.6503 21463584 VoipVoice::getDefaultVoice( ) ../voipvoice.inc:94
87 0.6503 21463660 VoipVoice::getVoice( ) ../voipvoice.inc:64
88 0.6505 21465732 _drupal_error_handler( ) ../voipvoice.inc:89
89 0.6506 21465732 _drupal_error_handler_real( ) ../bootstrap.inc:2226
90 0.6518 21476324 _drupal_log_error( ) ../errors.inc:90
91 0.6518 21476516 watchdog( ) ../errors.inc:217
92 0.6519 21478376 module_invoke( ) ../bootstrap.inc:1740
93 0.6520 21479664 call_user_func_array ( ) ../module.inc:799
94 0.6520 21479916 dblog_watchdog( ) ../module.inc:799
95 0.6522 21484772 InsertQuery_mysql->execute( ) ../dblog.module:154
96 0.6525 21486300 DatabaseConnection->query( ) ../query.inc:36
97 0.6525 21488392 DatabaseConnection->prepareQuery( ) ../database.inc:663
98 0.6526 21488884 PDO->prepare( ) ../database.inc:464
99 0.6526 21490380 DatabaseStatementBase->__construct( ) ../database.inc:464