I'm unsure whether ice will have any effect as the components that need cooling are
inside the case. Adding airflow in the form of a fan will push cooler air in via the ventilation grilles/slots thereby cooling the tuner and other associated parts inside. Also if you can increase the clearance below the unit by, for example, putting the
Skystar USB on some coins that may help. Apart from that, I'm unsure what to suggest really.