It's Saturday night in Barcelona and despite Pep Guardiola's side leading Atletico Madrid 5-0, the rain isn't the only thing putting a dampener on the atmosphere. Barca may boast the highest average attendances in world football at almost 80,000, but Camp Nou is far from a seething cauldron of noise.
Many of Barca's match-going fans are middle class and middle aged. They view going to the match like going to the theatre, where they expect to be entertained before they applaud. The thousands of football tourists who watch games are frequently blown away by the football and the huge stadium, but left underwhelmed by the unexpectedly flat atmosphere.
There have been two exceptions at Camp Nou, two different groups of vocal fans who've stood and sat behind each goal on the bottom of the six levels of seating.
The highest profile group were the Boixos Noix, literally 'Crazy Boys' in Catalan. They drank and sang and followed their team home and away. The club helped them with tickets and travel, while turning a blind eye to their indiscretions. It was and is much the same all over Spain.
Joan Laporta changed all that when he took over the Barca presidency in 2003. He stood up to the Boixos and told them they had to pay for match tickets, while denouncing their violence. The vast majority of the Boixos stopped going to games in protest and the atmosphere suffered. The few dozen who stayed in a section of 1,400 seats hollered anti-Laporta chants for years.
It was weird watching the brilliance of Ronaldinho et al against a backdrop of sustained abuse towards a president presiding over the club's most successful ever period. Laporta had death threats daubed outside his family apartment and needed protection. Boixos flags continued to be seen at matches and members would turn up at the Barca hotel on European away trips and make their presence known, but they were a diminished force.
Whatever the rights and wrongs, Camp Nou's atmosphere continued to suffer. There is an ultra group at the other end of the stadium called the Almogavers. They are named after the Catalan invaders who dominated the Mediterranean in the 13th century, but they rightly denounced violence. They waved flags and sang at matches, but compared to big Italian or Turkish stadia, the elephant-sized Camp Nou made a mouse-like squeak.
Barca decided to act this summer. Aware that the average age of their match-going fans was increasing, a new 'young stand' was proposed for loud, passionate fans who felt excluded by Barca's success and the eye watering ticket prices if you weren't a season ticket holder.
The club proposed that tickets would be 50 per cent of their usual price and allocated 1,400 seats behind the goal. A new supporters' club was planned with up to 4,000 members - and it was from these that the banner-waving, chanting fans would come.
Explaining the idea, one of Barca's vice-presidents, Jordi Cardoner, said: "It is designed to make the support in our stadium more heard. Sometimes we are lacking in volume at difficult times. Perhaps it's because we Catalans sometimes find it hard to express ourselves collectively.
"Our stadium needs the kind of support that our team deserves. Many other teams have much noisier supporters than we do, and our team deserves more."
Cardoner added that the section should reflect "Barca's support, Catalanism and civil duty. We want the very best support for our team. Not accepting this project would be like giving in to violence. We have the best fans in the world and we should have the best stand in the world."
He was preaching to the converted, but Barca do not have the best supporters in the world. There are clubs all around Europe which take far more away fans to games than Barca and whose fans make far more noise, but there was much interest in the project.
That was until the Catalan police looked at some of the names of the people hoping to join, identifying many with criminal records and many former members of the Boixos. The police said they wouldn't sanction the idea until Barca could guarantee the concept was safe. Which means not filling a stand with madheads.
Barca also announced that they are banning smoking at the stadium and they hope to increase the ground capacity by 7,000 seats to 105,000 by 2015. Crowds are increasing and the demand is there for tickets for most matches, but some of the fans should be local and vocal rather than monied football tourists from Northern Europe.
Barca are not the only big Spanish team spending on their ageing home. Real Madrid announced plans at the weekend to clad the exterior of the Santiago Bernabeu in a manner similar to Bayern Munich's stunning Allianz Arena.
The 80,000 capacity won't be increased (if the seats in the Bernabeu went any higher they'd be a danger to passing aircraft) but the stadium will be fully covered, look more modern, more striking and befitting of its location on one of Spain's grandest avenues.
But as Barca have found out, it's the people inside a stadium which make it, not the colour or structure of the stands.