Thankfully it's still at 6dB.
I managed to get a couple of traces (ignore the scale - I haven't managed to get that right yet . . .)
The sync speed graph shows 7520 in green (the speed at which I initially sync'ed with the exchange) and in blue the current speed that I would sync at.
The SNRM graph starts at 6 dB, then drops down to 5dB at 20:00h, 4dB at 21:00h, comes back up to 6db at 5:30 in the morning and finally reaches 7dB at 6 o'clock in the morning. No idea what time the street lights come on or if indeed this performance is related to them, but there's nothing else happening at home that I can think of which could have this impact.
EDIT: Oops, forgot the snrm graph - now added.
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