@neg3ntropy 

Hi, 

Have you tried to enable the guest network and tick 'enable QoS for guest network', then connect the client to the guest network to upload the large files?

Thank you very much and wait for your reply.

@neg3ntropy 

Thanks for your update.

I would like to forward your case to the senior engineers.

Could you please help me check the following details:

1. Did both wireless and Ethernet connection drop out when the Qos is enabled?

2. How about the dropping frequency of the Archer VR2800v, like 3-4 times a day?

3. Would there be an error message when the connection dropped and how did you restore the connection?

4.If possible, could you please log into the modem and save the log for me when the connection got lost;

Thank you very much and wait for your reply.