HP 9500mfp manual Are you using a phone-line splitter?, Are you using a surge-protection device?

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•Roll-over lines: A phone system feature where a new call “rolls over” to the next available line when the first incoming line is busy. Try attaching the fax to the first incoming phone line. The fax will answer the phone after it rings the number of times that is set in the rings-to-answer setting.

Note	Roll-over lines can cause problems with the ability to receive faxes. HP recommends that you do not use
	roll-over lines.

Are you using a phone-line splitter?

Parallel or “T” phone-line splitters should not beused with the fax because they can degrade the quality of the phone signal.

Are you using a surge-protection device?

A surge-protection device can be used between the wall jack and the fax to protect the fax against electrical power that passes through the phone lines. These devices can cause some fax communication problems by degrading the quality of the phone signal. If you are having problems sending or receiving faxes and are using one of these devices, connect the fax directly to the phone jack on the wall to determine whether the problem is with the surge-protection device.

88 Chapter 4 – Faxing Rev. 1.0