In regards to Definitve ProSubs, it is not actually a design flaw but it is much more of application based design overlook. In the US and other western countries, they don't turn-off the unit already even if, it would be days before they used the sub again. Thus, the busting of fuse is lesser compared to asia. Moreover, in Asia, especially in the Philippines, the powerfluctation is quite extreme. As per our test, even such big malls, the power fluctuation registered from 150V - 320V. The situation got worse because most of the Asian user have not reported it to Definitive regarding their changing of fuse...previously the standard fuse by Definitive is 1.25A slow blow fused. The distributor usually recommend to replaced it with 5A to the end-user. This result to such action is the burning of the built-in Amp. Currently the fuse standard equipped ProSub is 1.65A slow blow type.
In the Philippine market, there is no avaiable slow blow fuse, we normally ask Definitive for this.