I agree regarding the SNRM, DLM is unlikely to do anything (improvements if you're banded) unless it's much higher. HG612's certainly have been known to produce intermittent blips of packet loss on lines connected to ECI DSLAM's, so I would only recommend using HG612's with ECI DSLAM's as a method to get detailed statistics about your connection.
I would recommend swapping to either a DrayTek Vigor (I use the 2860 currently on 'vector4' firmware which has a newer modem firmware) or an ECI /r modem, both of which have the same chipset vendor as the ECI DSLAM. The former however will give you some statistics about your line, where the latter won't really (easily) unless it happens on be on LEDE firmware. In my experience, for my own connection (which is strange), the DrayTek performs the best in terms of stability. Slightly less attainable speed but I believe that's due to the fact the HG612 doesn't appear to use reed solomon coding 'R' on the downstream when on fastpath where the DrayTek does (and probably any other modem using an Infineon/Lantiq chipset). The unlocked ECI /r with LEDE firmware showed the same instability as the HG612, as did a Zyxel when I tried that too, so unless your line is good/reasonable then I don't feel I can recommend devices with a Broadcom chipset. An ECI /r on the standard locked or unlocked non-LEDE firmware should be fine though. You can also adjust the downstream SNRM target offset between -5 to +5 dB on the DrayTek, which is nice if you want to try and squeeze more speed or have more stability on your connection.
Your attainable rates may well be a little lower than average as previous reply stated. For comparison, my downstream attenuation is 16 dB and I'm getting an attainable rate of 82117 downstream (probably nearer to around 90000 if I didn't have reed solomon coding 'R', and yes I am on fastpath) and 24090 upstream last I checked. I'm curious to know what your DSLAM's (line card actually) firmware version is, generally I believe most ECI connections are on 0xb206 but there are some which are on 0xd086 like me. You can fetch this with 'xdslcmd info --vendor' (without quotes) if connected to the modem via telnet, or alternatively on DSLstats on one of the tabs (Stats?) though I can't remember the exact name of the tab.