Scalablelist: Index 0 outside the allow range [0::-1]

I've read though other threads regarding this error, but mine seems to be a little funky. I have a pretty complex report with many parameter. In Visual Studios, when I try to preview the reports under any parameter, it has no issues generating it and I can preview the report fine. However, when I try to export to PDF under certain parameter options selected, I receive the following error: 

"An error occurred during local report processing."

"An error occurred during rendering of the report."

"An error occurred during rendering of the report."

"(processing): Scalablelist: Index 0 outside the allow range [0::-1]  "

This only happens under certain parameters for some reason. Under other parameters, it will export to PDF just fine.  What is going on here?

Edit: When I try running the report in SSRS, this is the stack trace message:

[ReportServerException: An internal error occurred on the report server. See the error log for more details. (rsInternalError)]
   Microsoft.Reporting.WebForms.SoapReportExecutionService.ServerUrlRequest(AbortState abortState, String url, Stream outputStream, String& mimeType, String& fileNameExtension) +1018
   Microsoft.Reporting.WebForms.SoapReportExecutionService.Render(AbortState abortState, String reportPath, String executionId, String historyId, String format, XmlNodeList deviceInfo, NameValueCollection urlAccessParameters, Stream reportStream, String& mimeType, String& fileNameExtension) +1121
   Microsoft.Reporting.WebForms.ServerReport.InternalRender(Boolean isAbortable, String format, String deviceInfo, NameValueCollection urlAccessParameters, Stream reportStream, String& mimeType, String& fileNameExtension) +425
   Microsoft.Reporting.WebForms.ServerModeSession.RenderReport(String format, Boolean allowInternalRenderers, String deviceInfo, NameValueCollection additionalParams, Boolean cacheSecondaryStreamsForHtml, String& mimeType, String& fileExtension)+209
   Microsoft.Reporting.WebForms.ExportOperation.PerformOperation(NameValueCollection urlQuery, HttpResponse response) +219
   Microsoft.Reporting.WebForms.HttpHandler.ProcessRequest(HttpContext context) +222
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +586
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +177