USB hub behaving weird

[Lumia925]

I purchased this USB hub like a couple of weeks back, it was working fine.
Since this morning, it's behaving weird. I have 2 devices plugged in to it, a microsoft optical mouse, and a 3G internet dongle (looks like a flash drive).
Both devices stop working and Windows repeatedly plays the USB connect/disconnect chime for a while, followed by a message saying "USB device has malfunctioned".
This happens when I plug in the 3G modem.
I've tried with other devices- flash drives and keyboards, the problem cannot be reproduced.
But If the modem is connected to one port, plugging any other device will either instantly trigger the failure, or after a while.
I've also discovered the hub gets extremely hot, feels like it's about to melt the plastic casing - when i have the modem connected.

Connecting the modem alone doesn't trigger the problem, it's triggered if i have another device (the mouse) connected as well.

Connecting the modem directly to an unused USB port on the laptop itself, doesn't trigger the problem either, the laptop doesn't even heat up near the USB port.

Here's a screenshot of the USB properties/ power tab in device manager:

Why's this happening?

PS: Although it says "HUB is self powered" on the screenshot, the hub doesn't have an external power source connected to it, it's drawing power from the laptop itself.

 

[boosted1g]

Its no mystery. You bought a cheap no-name brand adapter that is a garbage.
The usb modem is pulling more power then your flash drives as it has to power a transmitter and receiver for your cellular connection. The junk usb hub cant handle it and it gets hot and does not work properly.

 

[Lumia925]

Scoured the user's guide (riddled with grammatical errors) , this issue isn't covered.
Managed to find a warranty support phone number though.
And guess what happens when I call them--- "beep beep beep, this number is not in service, please check the number you've dialed".

LOL 😀

Is it okay to use this hub with flash drives, mice and keyboards? Things which don't heat it up much? Or shall i just throw it away??

 

[boosted1g]

Do what you wish, but I would not plug something with that low of build quality into my computer. A short on the USB port can cause all sorts of issues for a motherboard.