Wyse 3040 - no sound from integrated speaker

Hello, i am testing 3040 for my company, i configured the unit from WMS and we connect to Citrix Xenapp. everything works fine apart from sound, which works only with external speakers/headset. btw, i can't find on DELL 3040 documentation if it has internal speaker at all - from zero launchpad, in peripheral options, i can see the checkbox "speaker" grayed out. - sound is enabled in BIOS Thanks!