Troubleshooting: answers from the support forum

Answers to the questions most often asked in our former support forum. More help is available in the support documentation.

The bell of my Opis 60s mobile is too quiet – can the volume be adjusted?

The ringer volume cannot be adjusted: the 60s mobile has a genuine mechanical metal bell with a clapper, not a loudspeaker. The volume is roughly that of a telephone from the 1960s. Place the phone on a hard, even surface (for example a table) – this makes the bell much louder. If the phone is still barely audible, there may be a technical problem. In that case contact our support and include the serial number (printed on the underside).

My Opis 60s mobile has no dial tone – it rings but I cannot answer.

Most often the receiver switch is stuck, for example after rough handling in transit. Check whether the contacts at the cradle come all the way out when you lift the receiver. If they do not, you can fix it in a few minutes with a screwdriver: remove the four feet with a Phillips screwdriver and detach the bottom plate – two videos show how: video 1, video 2. Also check that the battery is charged. If the problem remains, contact our support with your order or invoice number – we will repair or exchange the phone.

I can receive calls on my Opis 60s mobile but cannot make calls.

If several working SIM cards all only produce announcements such as “this number is not assigned”, the phone is probably defective. Please contact our support with your customer number and serial number (starts with SN and is printed on the underside of the device).

The Opis mobile does not recognise the SIM card.

First try the SIM card in an ordinary mobile phone. If it works there, the problem is with the Opis. If the SIM LED stays on permanently although the card is fine, the contacts are usually the cause: carefully bend them up a tiny bit with a needle so they press better. If that does not help, contact our support.

The Opis mobile does not charge, or the battery LED stays on permanently.

Remote diagnosis is difficult; these checks help narrow it down: Is there 5 V at the charger? Does the charging lamp on the underside light up? Does the LED stay on after unplugging the charger or after a restart (switch off and on)? Do you hear the three-times “charge critical” signal (see manual)? If the charger is faulty you can order a new one in the shop. If the problem remains, contact our support and describe what you observe.

My Opis 1921 cable or 60s cable only rings briefly and the call drops.

Possible causes: the phone is defective (for example a component in the ringer circuit), or the ring signal from your router does not meet the standard – our phones work with most routers, but we could not test all of them. If several phones are connected in parallel on one line, they share the ringing voltage. Try another socket or location. If the problem remains, the phone is probably defective: contact our support with your order number and we will send instructions for repair or exchange.

My landline phone crackles, hisses or hums.

Possible causes are a defective phone or interference from the surroundings (refrigerator, radio devices, power supplies without interference suppression). Test the phone at another location, for example at a neighbour’s. Route the cable to the wall socket away from other electronic devices; ferrite filters can help. Switch off possible sources of interference nearby as a test. If the problem remains, the phone is defective and will be replaced – contact our support with your invoice number.

One digit (for example 1) is not recognised when dialling.

This can be an incompatibility between the phone and the line (rare) or a defect of the phone. In both cases we will help: contact our support with your order number and we will send you a replacement phone.

The Opis 60s micro hisses with the USB-C adapter or on a computer.

The adapter is an active electronic circuit: it converts the signal between phone and handset from digital to analogue and back. If it does not work properly or does not recognise the handset, there is noise or the other party cannot understand you. Try a different adapter; some phones do not recognise the handset at all. On a computer, the sound card drivers can be the cause – install the mainboard manufacturer’s drivers instead of the automatically installed Windows drivers. Suitable adapters are available in the shop.

My Opis FunkyFon Cable does not dial – is there a switch between pulse and tone dialling?

The FunkyFon works with tone dialling (DTMF) only; there is no switch. If dialling does not work, these questions help: Do you hear a dial tone when you lift the handset? Does the phone ring when called? Is there a connection when you answer? Also test the phone on a different line. If you use a router, the phone must be plugged into its analogue telephone socket and the router must be set up correctly. If the rotary dial does not dial correctly it is probably defective – then contact our support and we will send a replacement.

Does the Opis 60s cable have a ringer on/off switch?

Yes, all current models have a switch to turn the ringer on and off. Very old units (before 2016) did not always have it.

How do I switch off caller ID on the Opis mobile?

Caller ID is a function of your mobile network provider, not of the phone. Ask your provider how to switch it off permanently: often there is a dial code you enter after lifting the handset, or a setting in your online account.

My Opis mobile does not connect to a network although the SIM works in a normal phone.

The classic models are 2G (GSM) phones. Check whether your SIM card and network support 2G – some providers have switched it off or do not offer it. An ordinary mobile phone switches between 4G and 2G automatically, so a test there is not conclusive. If you need a phone for a 4G-only network, choose a 4G model; a decision guide is on the page 2G or 4G? If the SIM LED stays on, check the SIM contacts or contact our support.

The handset cable is faulty – can I get a replacement handset?

Yes. contact our support with your order details and, if possible, a photo of the damage; we will send you a replacement handset.

May the Opis mobile stay permanently connected to power?

Yes, that is no problem. The charging chip in the phone controls charging automatically; most customers leave the phone permanently on its power supply.

What is the R key on the Opis 60s cable for – and how do I transfer calls?

The R key is not a flash key; it is redial. To switch or transfer calls, press the hook switch briefly (hook flash) – this works for example on a Fritzbox.