trust me, i feel your frustration, brother. I've had more than my fair share of troubles with cable and TSI.
and i really don't know what to recommend to help - you can keep pushing for more and more tickets, hoping that TSI can get Rogers to send out a tech who knows what they're doing who might be able to sort out the source of your trouble...
but if it only happens at night, that might be tough even for a competent tech... and we know that not all the techs are competent
and if its really an intermittent problem with the line, switching to Rogers probably isn't going to help anything, other than maybe getting more money out of your wallet... so what do you do?
i wish i knew. i'd say switch to DSL but that might be asking for a whole new set or problems with a different incumbent