Earth Changes
Fire crews were called to the scene on Tuesday at around 8am after reports of loud bangs and smoke.
Communters reported hearing two bangs and witnessed smoke rising from a drain close to the Apple shop.
An area at the junction with St Vincent Street was sealed off while firefighters investigated the cause and discovered there was a fault with an electrical cable about a metre underground.
Scottish Power workers were called to deal with the incident.
A company spokesman said said all properties affected had been re-connected by 09:25 and there was "no evidence of any explosion".
A spokesman said: "We apologise for any inconvenience. We will now work to repair the cable fault.
"There was no evidence of any explosion. A bang was heard but the fault occurred several feet underground."
Strathclyde Partnership for Transport said the situation "resulted in a power surge affecting signalling" on the city's subway and warned of delays to services.

Fort McMurray's sky turns orange as fire forces oil workers to evacuate camps.
According to the BBC, more than 8,000 people were urged to leave the area on Monday night, in addition to 4,000 people who had already been issued with evacuation orders.
Suncor Energy Inc was among several operators which confirmed on Tuesday that it had been forced to shut down operations as a precautionary measure.
A spokesman said there had been no damage to the company's assets and that fire defences were in place around the facilities.
Suncor and Syncrude Canada also confirmed they had evacuated workers from the area.
"Suncor has enhanced fire mitigation and protection around all of its facilities," one Suncor official told AFP.
"When it is safe to do so, we will continue implementing our restart plans," they added.

People walk through a flooded road after they moved out from their houses in Biyagama, Sri Lanka.
Strong winds, lightning and falling trees have also caused major damage.
Sri Lanka's Disaster Management Centre (DMC) report said that since 13 May, over 200,000 people have been affected, with 134,000 currently displaced and staying in 176 relief camps set up for the victims. Almost 1,300 homes have been damaged and 68 destroyed.
DMC said in a report yesterday that at least 8 people have died in the severe weather since 13 May, with at least 9 more still missing. One person died in floods in Wattala, Gampaha, Western Province. Four of the deaths occurred after a landslide in Dehiovita, Kegalle, Sabaragamuwa Province.
The bird, also known as a bearded vulture, is typically found in mountainous areas in Europe, Asia and Africa.
The bird was seen at Sudbrook in Gwent on May 12, and a few days later over Dartmoor.
If the sightings are confirmed as a wild bird, it will be the first time one has ever been seen in the UK.
Watch the lammergeier in flight near the Severn Estuary. Video courtesy of Dale Kedward.
With walls of packed sands falling over and on people and buildings from as high as 100 meters, visibility was reduced to arm's length at best. Local meteorological authorities issued an orange alert the second highest severity. Massive sandstorms have hit Tumxuk City and Minfeng County in northwest China's Xinjiang Uygur Autonomous Region since Monday.
A powerful sandstorm swept Tumxuk on Monday evening. Videos shot by local residents show that a huge amount of sand and dust was blown about a hundred meters high, and the visibility on roads was reduced to less than five meters.The sandstorm lasted for four hours with strong winds, dusty weather and temperature slump.
Affected by a strong cold wave, a sandstorm hit Minfeng County in Hutan Prefecture at around 06:00 on Tuesday. The maximum wind speed of 9.4 meters per second lowered the visibility to less than 60 meters, destroying trees and billboards along roads.
Comment: Some other sandstorms to hit China in recent weeks include:
- Massive sandstorm sweeps through China's Xinjiang, Qinghai
- Sandstorm blankets Guazhou, China
- Powerful sandstorm turns city red in northern China

Rescuers recover the body of a victim after a flood hit Dua Warna waterfall in Sibolangit, North Sumatra, Indonesia, Monday, May 16, 2016. Nearly two dozen students were missing in rain-triggered floods and landslides at the waterfall which is popular tourism attraction among locals.
One student was found alive and was being treated at a hospital, said Darwin Surbakti, an official from the local Disaster Management Agency. The search for the four people still missing was to be resumed Tuesday.
"Rescuers have discovered 17 bodies, of which 14 have been recovered while three others are still under the rubble," Surbakti said.
The disaster occurred Sunday as more than 70 students were visiting the Dua Warna waterfall in Sibolangit in North Sumatra province.
Six bodies were found about 3 kilometers (2 miles) downstream from the waterfall, Surbakti said.
The victim couple, Mukesh Hembram and Suhagini Soren, along with their seven-month-old daughter were returning to their home at Jamjori when rain accompanied by thunderbolt lashed the area, Officer in-charge of Jamjori police station, Rampukar Singh said.
The couple took shelter under a tree near a pond where they were struck by the lightning, he said, adding, they were killed instantly while the child fell from her mother's lap and escaped death.
The child was reported to be safe, Singh added.
Source: PTI

Naval officers monitoring the islands of Hawaii before an imminent hit by a tsunami following a powerful earthquake off Japan, in the port city of Valparaiso, 120 km northwest of Santiago.
Researchers at the University of Hawaii at Manoa have found that there is slight, but potential chance of about 6.5-12 percent that a 9+ magnitude earthquake will rock the Aleutian Islands and trigger a mega-tsunami that could easily reach Hawaii, disrupting its infrastructure and economy, the study published Friday in the Journal of Geophysical Research says.
According to the Sonoma County Sheriff's Office, the dead whale was spotted at Salmon Creek Beach by crew aboard one of their helicopters on Monday afternoon.
Neither the type of whale nor the cause of its death was immediately reported by the Sheriff's Office.
Today, our helicopter Henry1 spotted this dead whale in the surf at Salmon Creek Beach pic.twitter.com/3bUY1k7rO3
— sonomasheriff (@sonomasheriff) May 16, 2016
At least 81 people were killed by lightning strikes in Bangladesh in two days during the recent spell of thunderstorms, a rare high casualty in the country attributed to climate change by the authorities.
"Such a high casualty figure in lightning just in two days is rare not only in Bangladesh but also in the world,"disaster management minister Mofazzal Hossain Chowdhury Maya told a media briefing at his office. "The intensity of lightning has increased in recent years due to climate change sparking a massive public fear," he said.
Secretary of the ministry Shah Kamal said that the government included lightning in the list of natural disaster since August last year in view of its growing intensity claiming 81 lives on May 12 and 13 alone in 26 districts. Most of the deaths occurred in rural parts of north and central Bangladesh. According to official count, lightning killed 17 people last year.











Comment: ANOTHER electrical incident at Washington DC metro station - This time sparking 'fireball'