Based on the records, we've used a different copper pair between the TPG exchange and to your premises to avoid interference external to our network which we do not have control over. We've also used a different port at our DSLAM. We do this by relocating the your services to the same address.
Let us know should you need further assistance.
Thanks for your info. I'll see how is it going with another provider and will let you know if I get any clue about the cause. Btw the dropout seems to occur frequently during the peak time (6-8pm).