Some telephones work regardless of line polarity, others require that it be correct. All modems require correct line polarity, as does a DSL connection. I don't know that this is the problem but I have seen it happen before.

DSL is always preferable to dial-up because of the speed; however, it is much more expensive. You can get dial-up plans for as low as around $10 a month whereas DSL is a minimum of about $35 and can be as high as $50 to $60, depending on carriers in your area.

~ GaySatyr

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