Your downstream levels are 10-14 (should be as close to 0 as possible) and your upstream levels are 23 (very poor, should be closer to 38-45).
Your snr is 38-39 which is pretty good (higher the better but I'd say yours is above average).
Even with those downstream levels, it's still usable. However the upstream levels are far far too low. Your modem is disconnecting because of this.
I come from a heavy gaming background so it pains me to even read this thinking about gaming on it. I can't possibly imagine the latency and packet loss issues. Ugh.
I have outlined a solution below, but it is based on the assumption that the coax from your wall is going directly into the modem with no splitters or anything in between. If there is anything between your modem and the coax coming from your wall, let me know.
So here is what you'll need to do. You have a couple different options but I've only listed the most cost effective method below. You will need to purchase the following:
- A good quality Coax cable. You will need one short one, maybe 1-3ft or less, and one long enough to reach your modem.
Reasoning: Although signal levels are mainly something that is out of your hands and something that ISPs have to fix, there should not be this much fluctuation/spread between your downstream levels. Purchase a double or triple shielded coax cable to prevent any noise or ingress from your end.
- A good quality 5 way splitter. None of that gold plated gimmicky nonsense (although most gimmicky splitters are often advertised as gold plated, not all gold plated splitters are gimmicky). The range of the splitter should be at least 5-1050 if you only have a modem connected to the splitter, and at least 5-2050 if you have a modem and TV line connected to the splitter.
Reasoning: With every split you make, upstream levels increase by 3.5 and downstream levels reduce by 3.5. With a 5 way splitter, your upstream would increase to 37.5 which is at our targeted range and your downstream would decrease to -1 which is also in our targeted range. 5-1050MHz range is where internet operates 1050-2050 is typically where TV operates. You don't want the two mixing.
- Optional but highly recommended purchase: MoCA filter
Reasoning: Prevents excess noise and leaks from neighbors and others coming onto your connection. Although that SNR is decent, I'm sure it takes dips during peak hours when your neighbors and those on the same node as you are on it. Although the filter won't prevent congestion related issues, it will prevent signals from those homes crossing into yours and vice versa.
- Optional but highly recommended purchase: Coax caps/terminators
Reasoning: The empty ports on your splitter will also throw some noise into the line so caps/terminators to cover those ports are recommended to prevent that.
All in all, your new wiring should look like this:
Before - Coax port in wall --> coax cable --> modem --> ethernet --> router
After - Coax port in wall --> MoCA filter --> shielded coax cable (short) --> "IN" port of 5 way splitter --> "OUT" port of 5 way splitter --> shielded coax cable (length to modem) --> modem --> ethernet (hopefully already cat 5e or above) --> router
Congratulations your line just became 10x more strong and stable than before along with in line signal levels.
I'd post the links to these products but I'm not sure if I'm allowed to. Hope I solved your issue and let me know if your wiring situation is different than what I presumed.