Hi all, wondering if anyone here would be willing to share their thoughts on some unusual ADSL issues I have suddenly been experiencing.

A few days ago I noticed frequent DSL drops, I went ahead and reset the modem, reconfiguring with ISP recommendations. Since doing this I have had no internet connection whatsoever. I also have a phone line which was working fine several days after the internet went down, but now Ive noticed that when calling out there is dialtone, a single sound (almost like that of an engaged line) followed by a continuous engaged tone. I have noticed that this only occurs on 0800 numbers or when using the regional prefix ie. (09) If i call a local number without any prefix there is no issues with the call. (I couldn't find any posts regarding this or any similar issues).

Having done various isolation tests and changing different cables, trying other phone jacks etc I am left rather clueless. My first thoughts would be that there is some issue with the wiring, as flooding did occur under our house about a month back. My next step advised by my ISP is to log a Chorus callout to check between the demark point and the exchange. I am just wanting to check if I am missing anything at this stage. Greatly appreciate any thoughts/suggestions on this matter.