Reset Modem?

[#1]

Another day, another slight drop in Down Speed, the speed is falling a tad  day on day.  Up Speed also dropped in line with down speed but has begun to increase ever so slightly this morning. IP Profile on BTW Performance test remains at the increased level of last week, so why the dropping speed, and is there anything that I can do to at least restore last week's improved performance?
I wonder about resetting the modem?
In my ignorance, I think that the port in the Cabinet needs a reminder to stay awake, a prod, although that generally brings DLM into play and DLM seems to never let go of any speed it grabs hold of. Also in my ignorance, I wonder if BTO set DLM to kick in and take load off an overloaded network thus slowing improvement expenditure. That sounds daft to me too, but why the slowing speeds in a world opening up to even faster communication and the possibilities that brings?
Yesterday, speeds fell badly at one stage but recovered again later BTW test showed a red line. One expects small variations but not half speed and why the creeping slow down?

[#2]

It slows down simply due to the fact that you're running a 17Mhz frequency over copper and with hundreds of other peoples pairs sat directly next to each other. The holy grail of crosstalk and the not so brave BT who take years and years to trial things that they release in a depricated state anyways.
Of course it's not always crosstalk related, could be a variety of other weird factors.
If you can post some stats from your modem/router, that would help the forum experts and staff a lot.

[#3]

Thanks for your reply NoZephy. I'm not generating stats to post now, that I'm using a remote BTO Huawei modem,  I did previously when I used the built in modem on my ASUS DSL-AC68U, but changed back to the Huawei when it was suggested that the ASUS could be slowing my connection.
A number of times its been suggested that running my current set-up and waiting would see speeds increase, waiting for weeks, and then 2 weekends back, I saw speeds increase slightly, and my IP profile "moved up one notch" on BTW Performance Tester. From 37.04 to 40.75. I thought I'd "arrived"! 37.04 had been a cast-iron profile for months, unwavering and I was amazed that another was possible.
I'm no expert, but one learns when things aren't right and you delve.
To keep it brief, many months ago we were switched to another port on the cabinet card after a severe thunderstorm, when our port failed,and the speed has been an issue since. Noise was being generated on our original port. I would dearly like to know what others connected to my cabinet are experiencing, I would not be surprised to find that our card isn't performing at its best, not surprised at all.
But I'm guessing.