@s55
you've posted two line conditions, in first when SNR are low your uptime is also low, as your SNR increases your uptime increases, one thing is clear from here that your line flactuates, second its on 2MB, if your # is of fiber fine but if you are on copper and over and around 3 KM form your exchange it will make problem no matter what. third if you can verify from local exchange that they have installed Hwavei or ZTE DSLAM's, as a rule of thumb one should use CPE of same brand as DSLAM, your line specs show you are sync at RADSL which ideally have to be ADSL2+ (in most favorable cases only), your line does not support this very well, fortunately this can be compansated at your end to some extend, here i can only tell u what to look for coz not seen huawei router and if it would been ZTE i would give you steps, ok look for ADSL line modulation in advance setup, or ADSL connection, your router by default will be configured to sync on selected available modulations which are selected, deselect all and only use G.DMT, a preety basic modulation technique which means less syncing time, full bandwidth sync and hopefully less desyncing issue if your line is not all that wild