ABS are doing a recall on Vario base units from 2011/2012, as they may rip or tear when the airbags are activated.
Tests have shown that if not opened and/or activated for a long period, the Velcro fasteners on the airbag compartment sometimes end up gripping so much that inflating the airbag may rupture the airbag compartment rather than tearing open. If the the serial number starts with 612 or 712, you should contact ABS using the form in the link below, who will then send you new velcro straps.