Easy one first
>> b) get interleaving turned off
How many FEC errors (and other errors) are you racking up and over how long?
Turning off Interleaving is a simple request for the ISP to do.
>> a) get my SNR lowered back down to 6db from 9db
This "should" in theory be relatively easy to do.. but you may have a problem getting through to someone at BTBroadband who understands what you want doing :/
... and on top of that BT Wholesale seem to be refusing more requests to lower the target SNR back to default.
Certainly worth a try though.
The DLM in theory should recognise that your line is stable again, and over time the theory is that it should automatically lower the target SNR back down again, however there doesnt appear to be any particular fixed routine (or a least publicised) on how this is done. Some have seen it happen in a couple of weeks, some in a month... and theres also been some rumours that it may take error count into consideration.
>> If I was to move the line to Sky broadband, would these values get carried over or would I get a new set of default Sky values?
If you were on a Sky exchange, then no you start afresh since they have their own kit in the exchanges which they control.
Point to note though is that Sky will not turn interleaving off and all sky connections are interleaved.
Theres no info about the sky DLM and their profiles, but they do have different levels and you would start afresh.
You can ask to be transferred to a lower depth of interleaving, as their default level is very high.
