TPS61099: Exceeding Vout of TPS61099

Hi

My customer evaluate TPS610993.
But Vout has been 5.5V under Vin=1V.
I found the following thread and I required my customer to decrease Cout and delay timing to beacome the EN logic high.
But they can't delay timing to beacome the EN logic high on their application.
Are there any other methods to avoid this problem?

  http://e2e.ti.com/support/power-management/f/196/t/730005?tisearch=e2e-sitesearch&keymatch=tps61099