Upstream uses the lower tones is. It's very rare that lower tones have that low SNR. That line has something on or near it probably shorting to your line when it gets wet.
If your line has a phone on it you probably have a filter that splits the dsl from the phone line. The upstream on the DSL lower band is outside the voice frequencies so it may be filtered out.
hook up a cheap phone when the problems appear and listen. If you hear pops, clicks or low buzzing sounds the line has issues. -- Sarick's Dungeon Clipart
Unfortunately I do not have a phone to test this with, it is a dryloop setup so I do not have any filters or any devices besides the modem on the line.
The problem occurs 100% of the time though. The line upload never syncs up at the correct rate on a power cycle. I do not see this issue on the other line however.
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