Yes, its plugged in. We also had issues with the older white readers. We found that keeping them plugged into power helped out a lot.
I just received one and can't even pair it to an Anroid phone using the Shopify POS app. I can pair it with the phone itself using the Android OS, but that doesn't help when Shopify POS app still doesn't recognize I've pair the thing to the phone.
Shopfiy POS is a fitting name....
If you search the forum you will see a couple of workarounds and quick fixes for this. While not a tried-and-true permanent solution these methods to get things working again!