Don’t know if this will work but you could give it a try esp with the low signal symptom.
Try changing the signal that your modem router is broadcasting on. It could be that another wifi signal within range of your kit is interfering and hence why your download stops.
I had similar problems which increased in magnitude with the abundance of wifi networks sprouting up around my humble abode. Since changing the channel its now fine.
You will have to access the admin panel which will be like an ip address
The default channel is usually 6.
Change it until you are happy with your signal strength.
I hope this helps.