For the last 10 days or so I have been having awful Spark Wireless connections (the previous 6 months have been rock solid).

I have rung Spark on 4 occasions and each time it seems to a worse experience.

(I got put through to a supervisor at one point, but even she just gave lip service - I was supposed to get things escalated to 2nd level, but when I rang back there was no ticket..... :( )

But here's the the latest thing: I got to thinking... this is only awful when I'm working from home. In the evenings and weekends, it is comparatively OK. So today I did an experiment. The connection had been OK (not that I was using it much... such a nice day, we spent most of the day in the garden :D).

However, this afternoon, I thought 'maybe it's my work laptop causing the problem' (I can't see how. But this is the thing about science, you have a hypothesis and you test it). So I fired up the work laptop, and then browsed the internet as per normal on my personal machine. It dropped (eventually - maybe 20-30 minutes after turning on my work laptop, which is consistent with what I would see through the week). But it did drop. I shut down the work laptop and restarted the wireless modem and the connection came back.

SO:

1) Is it possible for a device on the network to kill the connection? Doesn't matter how they are connected. My work laptop is on ethernet. But when the connection drops, my personal PC also on ethernet also drops, and my wife's laptop on WiFi also drops. 

It's a weird experience too. The symptom is DNS lookup failure. If I have a 'ping -t 8.8.8.8' ALREADY running, it continues fine (no drops). If I start the ping while down, then the first few packet fail and then it goes thru. But all this time DNS fails.

or

2) Is this all coincidental and there's something else going on beyond my perimeter? I have 4-5 bars of signal strength the whole time. So it's not like I am in a poor coverage area.

The thought of ringing Spark help desk again makes my teeth grind :( - I had one guy suggest the most illogical troubleshooting steps (eg "your LAN is overloaded"  - weird, about 2 things are on wifi, 4 devices on ethernet (one of them is a printer) and traffic through the device at the time was about 190MB in 50 minutes - not exactly putting things under load).

I could understand  the problem if one of the device was trying to push massive amounts of data thru and thus flooding the wireless, but 190MB in 50 minutes is nothing. (EG, we play Minecraft as a family on Realms, and I pull down the world locally to run a map render, and that can come down at 4.3MB/s  without issue.)

Anyone got any thoughts on next steps? I admit it's been a while since I did desktop support, but this one has me stumped. Thanks in advance.