Phone thinks it's ringing when it isn't

Fogmatic

That is, the LED & screen (of our cordless Grundig SINIO 1 Dect phone) is flashing on & off continously (and saying '1 new call)', as if receiving a call, but it's not ringing.

The fault seems most likely to be with the phone handset itself; if people think it's a Voice over Internet issue, I'll go to the VOIP forum.
When I pick up the handset, I just get the dialling tone. Replacing it on the base station makes it beep twice before resuming the flashing (longish beeps, sounding very firm about something; I don't remember hearing that before in the 6 years we've had the phone). Sometimes there's a third, higher beep (I can't remember doing anything different). The only way to stop the flashing is to physically disconnect the phone.
When I ring the number from another one, the phone's 'bell' rings as normal (and the call proceeds normally). When the calls's finished, the phone resumes the continuous flashing.

It doesn't help that I don't know how long it's been going on. I first noticed it last night, but that was while (unusually) walking around in the dark (the flashing could have been going unnoticed lately, with so little darkness). During last winter's storms, some lightning did kill another cordless phone here. (And I realised the other day that another handset, an old-style one, had lost its ring so was useless; same storm maybe).

Just to make diagnostics even more fun, I started using Voice over Internet for the 1st time 2 days ago, and I'm using the Grundig for that. (We have one other phone still standing, but it's hard to dial fast enough with it for the VOIP system; the Grundig enables keying in the number before going live or whatever the expression is). We're using the new phone number we've been given, until our old landline number gets ported (any time now),
But I tried the Grundig with the landline today, and it makes no difference (apart from being able to hear every word with the VOIP!).

Anyone else had this phenomenon?

Mr. G

What are the models of the equipment you have?

Mr. G

Wait, clear all your voicemails first. That light is probably a message waiting indicator.

Fogmatic

Sorry - I forgot to mention there were no messages on either number (I checked both mailboxes at least twice). In any case, if there was a message there would have been a warbling ringtone when picking up the phone, instead of a steady one (on the landline, anyway - maybe it's slightly different with VOIP).

Our broadband is (fixed-wireless? Wimax? Not mobile). Beamed through the air from a mast to our receiver, & into the house by cable, & into the internet socket of a little (anonymous, mains-powered) black box, with my router plugged into its LAN socket; Linksys WRT54GC (making a wireless LAN).
Cable from an ethernet port in the Linksys to the ATA; a Vomino box, made by Goldstream, model HT701.

Number porting happening any minute now (11.10).

Fogmatic

Also forgot to mention that, apart from the phone being reset by virtue of being disconnected the other night (for about 6 hours), I removed its power lead and batteries for a while yesterday (no result).

It's on our original landline number now, and still making & receiving calls ok.
When I had it off the base station for a while today, it did the 2 beeps every minute or so, except while I was using it.

I'm hoping to pass a shop tomorrow that has cordless analogue phones in stock, and buy one to replace the one we had upstairs (if there aren't any I like there, it's over to online shopping, which will of course take longer). Once I get the alternative phone, it should help to sort out where the problem is.

It probably sounds trivial, but our place is open-plan (bedroom and all), and night-time at the moment is like being in private-eye's room in an old movie, illuminated by flashing neon signs. I don't mind that, but it would be nice to solve it for my spouse, who's a very light sleeper at the best of times!

Fogmatic

Maybe I wasn't clear in the 2nd sentence. The phone was on VOIP both before & after our number was ported, and behaved the same throughout.
I noticed (thanks to a ticking clock) that every 6 seconds the phone's screen lit up for 1 second; except for every 10th time, when the flash was much shorter. (Maybe the phone's got its clock and its calls in a twist?)

The shop had some cordless phones I liked (by Panasonic), and I got one with 2 handsets (one for upstairs), so was able to disconnect the Grundig. The new phone's behaving normally, so the problem must be with the Grundig one. We can do without that phone now, but it's a fairly fancy one and it goes against the grain to give up & throw it away just yet. (It could be handy on an extension somewhere, or for somebody else).

When receiving a call on the new phone, there's almost no delay between the caller hearing a ringing tone, and hearing the phone ring at our end. The Grundig was several rings behind; a nuisance, but I assumed it was something in the VOIP department, to check out later. But maybe it could have been interference? (At the same time as changing phones, I spaced the hardware out a bit & tidied up the cables; everything was in a tangled heap before that).

Mr. G

Try another phone (borrow from a neighbour or someone) to rule out the ATA first.

Press the down arrow to see what calls you've missed, that should clear it. I'ts just a missed call, possibly from ages ago.

Fogmatic

Mr. G wrote: »

Try another phone (borrow from a neighbour or someone) to rule out the ATA first.

I thought I could rule out the ATA, router etc, with the new phone being on the same system but not having the problem?

Deleted User wrote: »

Press the down arrow to see what calls you've missed, that should clear it. I'ts just a missed call, possibly from ages ago.

Thanks Maryanne. I'll try that when I can, though I can't remember the Grundig phone ever telling us about missed calls. I've just looked in the handbook, and the only reference to missed calls there is in a section about a call log, where the phone will apparently put callers' numbers. It only includes missed calls 'when a call also transfers the phone number'. (I don't know what that means).

Fogmatic

Deleted User wrote: »

Press the down arrow to see what calls you've missed, that should clear it. I'ts just a missed call, possibly from ages ago.

I reconnected the Grundig today and tried the down arrow, but it doesn't show missed calls like my mobile does; just the (empty) phonebook.

Suggestions by others that I've tried;
leaving myself a message, then clearing it;
calling the phone & hanging up before voicemail kicks in;
holding down the * key for a few seconds;
calling voicemail & hanging on through the entire menu, then pressing * to disconnect before hanging up.
But no differennce (screen still lighting up every 6 seconds with '1 new call' (but can only hear steady dialling tone), 2 beeps on hanging up, then back to the flashing).

Mr. G

Fogmatic wrote: »

I thought I could rule out the ATA, router etc, with the new phone being on the same system but not having the problem?

If that is the case where another phone does not have an issue, then obviously it is the cordless phone. Try reseting the phone to factory defaults and try again. May be some missed calls or something showing.

Fogmatic

Mr. G wrote: »

If that is the case where another phone does not have an issue, then obviously it is the cordless phone. Try reseting the phone to factory defaults and try again. May be some missed calls or something showing.

Thanks Mr G, that did the trick!

The phone's never notified us of missed calls, to my knowledge. Perhaps a power surge could have somehow created a false incoming call signal?