save_configuration iControl call failing

I created a PHP script to add and remove records from Data Groups. After it makes the changes it runs a SAVE_HIGH_LEVEL_CONFIG, this is where I am having a problem. Sometimes it saves the config and sometime it doesn't. I have looked through the logs on the F5 and there is nothing in the logs that help with the failures.

Here is the call to save the config:

$soap_config = new SoapClient($wsdl_config, array('location' => $location, 'login' => $user, 'password' => $pw, 'trace' => 1));
$soap_config->save_configuration("", "SAVE_HIGH_LEVEL_CONFIG");

Here is the PHP traces:

====Request Headers====
string(293) "POST /iControl/iControlPortal.cgi HTTP/1.1
Host: x.x.x.x
Connection: Keep-Alive
User-Agent: PHP-SOAP/5.3.3
Content-Type: text/xml; charset=utf-8
SOAPAction: "urn:iControl:System/ConfigSync"
Content-Length: 641
Authorization: Basic someauth==

"
====Request====
string(641) "
SAVE_HIGH_LEVEL_CONFIG
"
====Response Headers====
string(693) "HTTP/1.1 500 Internal Server Error
Date: Tue, 24 Nov 2015 20:09:11 GMT
Server: Apache
Set-Cookie: BIGIPAuthCookie=somecookie; path=/; Secure; HttpOnly
Set-Cookie: BIGIPAuthUsernameCookie=user; path=/; Secure; HttpOnly
SOAPServer: EasySoap++/0.6
X-Frame-Options: SAMEORIGIN
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Content-Security-Policy: default-src 'self' https://sentinel.whitehatsec.com https://api.ctscloud.com https://key.ctscloud.com 'unsafe-inline' 'unsafe-eval'
Strict-Transport-Security: max-age=16070400; includeSubDomains
Connection: close
Transfer-Encoding: chunked
Content-Type: text/xml; charset="UTF-8"
"
====Response Headers====
string(634) "


SOAP-ENV:Server
Exception caught in System::urn:iControl:System/ConfigSync::save_configuration()
Exception: Common::OperationFailed
        primary_error_code   : 16908289 (0x01020001)
        secondary_error_code : 0
        error_string         : Error saving configuration



"