Any idea why fully-charged DECT Panasonic cordless phones would
keep losing their wireless link lately?
http://farm4.staticflickr.com/3720/1...84d957e3_o.gif

They're not at all far (fifteen feet) from the base and, this
loss of signal only started happening about a year ago (the phone
is probably about three or four years old).

So, something clearly aged (but the batteries show as fully charged
and I've changed them between handsets anyway).

The error I keep getting (on multiple handsets) is:
No Link. Reconnect base AC adapter.

This happens after, say, a few minutes of talking time, but, it's
erratic. Sometimes I can be on the line for an hour before it
happens; other times it happens within five minutes.

What frustrates me is the lack of debugging techniques.

Reconnecting the phone to the charger doesn't change anything;
nor does placing each of the handsets back into the mother phone
to reinitialize them.

Here's the DECT Panasonic KX-TG6441 phone & handsets:
http://farm4.staticflickr.com/3779/1...40a29bee_o.gif

Here's the model number plate:
http://farm6.staticflickr.com/5539/1...f2dc22f0_o.gif

Googling for that error message, I see it's pretty common; but
I already tried the little that Panasonic suggests:
http://eng-na.faq.panasonic.com/app/...should-i-do%3F

The outlet is working fine; the phone works fine from the base;
it's just the handsets that keep losing their wireless connection.

Anyone else resolve this problem before?
Any debugging hints?