I bought the sound system for personal use. 
 
Since its first use, after about 15-20min of using it (with the volume low and high- I've tried both) it started to have a thumping/heartbeat sound. I've tried it in different places, from different devices and it always happens...It seems it comes from the subwoofer but not sure. 
 
I have to return it and wait for +1month to see if they can fix it. Meanwhile, I won't be able to use anything and already paid for it... 
 
The sound is good until it starts with the thumping, really annoying... 
 
Disappointed.