Ticking is the predominant sound inside Bala Muhammad's tiny watch-repair shop, tucked away on a bustling street in the northern Nigerian city of Kaduna.

It is like a time capsule from a different era with numerous clocks hanging on the wall and small tables at the entrance full of his tools and watches in various states of repair.

His shop is on one of Kaduna's busiest shopping streets - sandwiched between building material suppliers.

Until a few years ago, he had a steady stream of customers dropping by to get their watches fixed or get a new battery fitted.

"There were times I get more than 100 wristwatch-repair jobs in a day," the 68-year-old, popularly known as Baba Bala, told the BBC.

But he worries that his skills - taught to him and his brother by their father - will die out.

"Some days there are zero customers," he says, blaming people using their mobile phones to check the time for the decline in his trade.

"Phones and technology have taken away the only job I know and it makes me very sad."

But for more than 50 years, the boom in watches allowed the family to make a good living.

"I built my house and educated my children all from the proceeds of wristwatch repairing," he says.

His father would travel all over West Africa for six months at a time - from Senegal to Sierra Leone - fixing timepieces.

At one stage Baba Bala was based in the capital, Abuja, where many of the country's elite live - and he made a good living tending to the watches of the wealthy.

He reckons his best customers were top officials of the state-owned oil firm Nigerian National Petroleum Company (NNPC).

Some had Rolexes - these can vary wildly in price but an average one costs around $10,000 (£8,000).

He says they are beautiful - and encapsulate his love for all watches from Switzerland. He himself owns a Longines, another prestigious Swiss brand, which he only removes when he sleeps.

"If I step out of my house and I forgot it, I have to go back for it. I will not be without it - that is how important it is to me."

At his shop, he keeps a beautiful big framed photo of his father, Abdullahi Bala Isah, taken as he looked up from his work bench a few years before his death in 1988.

Isah was a renowned horologist and his contacts in Freetown and Dakar would call him to take a trip when they had enough watches for him to tend to.

He would also make regular visits to Ibadan, a metropolis in the south-west of Nigeria - a literary hub and home to the country's first university.

Baba Bala says no-one in the family knows where his father learnt his expertise - but it would have been at the time of British colonial rule.

He himself was born four years before Nigeria's independence in 1960.

"My father was a popular wristwatch repairer and his skill took him to many places. He taught me when I was young and I am proud to have followed his footsteps."

Baba Bala started taking a close interest in understanding the intricacies of what the wheels and levers inside a watch do when he was 10 - and was delighted to discover that as he got older it became a good source of pocket money.

"When my fellow students were broke in secondary school, I had money to spend at the time because I was already repairing wristwatches."

He remembers his skill even impressed one of his teachers: "He had issues with some of his wristwatches and had taken them to several places and they couldn't do them. When he was told about me I was able to fix all three of the watches by next day."

At one point, watches were seen as important as clothes in Nigeria and many people felt lost without one.

Kaduna used to have a dedicated area where many watch-sellers and repairers set up their businesses.

"The place has been demolished and is now empty," say Baba Bala mournfully, adding that most of his colleagues are either dead or have given up on the business.

One of those who admitted defeat was Isa Sani.

"Going to my repair shop daily meant sitting down and getting no work - that's why I decided to stop going in 2019," the 65-year-old told the BBC.

"I have land and my children help me to farm on it - that is how I am able to get by these days."

He laments: "I don't think wristwatches will ever make a comeback."

The youngsters working at the building supply shops next to Baba Bala agree.

Faisal Abdulkarim and Yusuf Yusha'u, both aged 18, have never owned watches as they have never seen a need for them.

"I can check the time on my phone whenever I want to and it's always with me," one said.

Dr Umar Abdulmajid, a communications lecturer at Yusuf Maitama University in Kano, believes things may change.

"Conventional wristwatches are no doubt dying and with it jobs like wristwatch repairs too, but with the smartwatch I think they could make a comeback.

"The fact a smartwatch can do much more than just show you the time means it could continue to attract people."

He suggests old watch-repairers learn how to grapple with this new technology: "If you don't move with the times you get left behind."

But Baba Bala, who returned from Abuja to Kaduna to set up his shop about 20 years ago as he wanted to be nearer his growing family, says this does not interest him.

"This is what I love doing, I consider myself a doctor for sick wristwatches - plus I am not getting any younger."

His tight-knit family remain loyal to his profession - his wife and all his five children wear watches and often pop in to visit him at the shop, where some of the timepieces on display are forgotten relics from old customers.

"Some brought them many years ago and didn't return for them," he says.

But Baba Bala refuses to give up and still opens up daily - his eldest daughter, who runs a successful clothes boutique nearby, helps him with bills when his business is slow.

Without much to keep him busy - or the chatter and gossip of his customers, Baba Bala says he now often listens to his radio for company, enjoying the Hausa language programmes on the BBC World Service.

In the afternoon his youngest son, Al-Ameen, comes to visit after school - the only one of his children to show an interest in learning the art of watch-repairing. But he would not encourage him to take it up as a profession.

He is pleased that the 12-year-old has told him he wants to be a pilot - continuing the family tradition of seeing more of the world.

In a cockpit, he would be faced with many watch-like dials - not unlike his dad's workshop.