For several days, people have had a hard time calling me. The phone
rings a bit then changes to a busy signal. Or once it sounded like
someone answers and then drops the phone

Then two days ago, I couldn't call out either. No dial tone.

But the DSL internet has worked the whole time.

Twice checking the NID, I got a dial tone.

In the last 36 hours, to fix my telephone, I replaced the phone, the
cord, the DSL filter, disconnected the main wire from the rest of the
house, and fiddled with the NID outside. Replacing the
one-piece, all-plastic, Y-connector for the phone line enabled me to
place calls again, even though I'm looking at it and it looks fine, and
I'd used it for years. But receiving calls still had the same
problems. I test by calling myself with Skype.

Once last night I called myself with Skype and the phone rang several
times and the phone machine (not voicemail) answered. . But then
receiving calls stopped working again. Then once today, the phone rang
twice at normal volume, but the phone machine didn't answer.

Now it's back to the way it was. When people call me, it barely chirps
and if I don't answer in what would be two rings, it gives them a busy
signal.

I've replaced everything that distinguishes the phone line from the DSL
line.


Could the DSL modem be messing up the phone, even though the phone
signal does not really go *through* the modem? It only touches the
modem input . That is, the phone line input and the phone output are
both in the same side of modular Y-connector, which plugs into the DSL
modem.

That is, the phone line from the NID goes straight to one of the two
"outputs" of a modular Y-connector. The "input" is plugged into the DSL
modem, and the other output goes to the telephone, via a DSL filter, a
cord, and a phone. I've exchanged the last 3 things and the Y
connector. What's left to replace?