Well, I dug deeper and found that the problem lies in the calling of functionFormatDeviceData in this line:
<td class="alternate_back" rowspan="5" valign="top" align="right">'.formatDeviceData($rowD['PK_Device'],$deviceDataArray[$rowD['PK_Device']],$dbADO,$rowD['IsIPBased'],0,1,'textarea').'</td>
And within the function formatDeviceData, the function serialPortsPulldown causes problem in this line:
$deviceDataBox.=serialPortsPulldown('deviceData_'.$deviceID.'_'.$rowDDforDevice['FK_DeviceData'],$ddValue,$rowDDforDevice['AllowedToModify'],getTopLevelParent($deviceID,$dbADO),$dbADO,$deviceID,$cssStyle);
And within the function serialPortsPulldown, the following line is where the hangup occurs:
$serialPortAsoc[$value]=SerialPortInfo($topParent,$value,$dbADO);
The values that are called by that function are:
$topParent = 63 (One of my MDs)
$value = pci0000:00/0000:00:1d.7+5.1:1.0
$dbADO = (blank)
(five minute delay)
$topParent = 63
$value = pci0000:00/0000:00:1d.7+5.2:1.0
$dbADO = (blank)
Not really sure what to make of this, but I'll look at it more tomorrow.