Mercy checks the gates and carvings.

Perception: 14

A squat stone gatehouse stands at the entrance to the dwarven city. Strangely, the gates are open. Beyond the gates, you can see an arched corridor that zigzags past sturdy stone walls where arrow slits squint from every angle. At the far end of this murderous hallway stands the entrance to this lost dwarven city.

You can hear...music, too.

Seeing the danger ahead, Mercy motioned to her friends to stop and move out of sight of the dangerous corridor. "That hall is a death trap. We need to take precautions..." She thought for a moment before pulling her hempen rope from her Bag of Holding. Tying one end around her wrist, she motioned Daewen over and did the same to her wrist. "If we do this right, we can get through the hall without the archers seeing us. We'll be blind, but we'll be safe." She tied her daggers to the rope, 15 feet from each end. Looking at Trini, she smiled reassuringly. "If you'll cast Darkness on that one, I'll get the other. We wait until we're ready to enter, of course. Daewen will creep along the wall of the hall and we'll follow, holding the rope to guide us. I've spaced the daggers so that the spells will overlap and hide us entirely."

Strife tries to identify whatever she may about the music.

Arcana (+4): 21
History (+4): 16

Daewen excitedly leads the roped group into the entryway...this is her kind of neighborhood, and she feels quite at ease in the gloomy darkness.

Perception check to see if she can spy any movement behind the arrow slots before the Darkness spell is cast: 17

 Once the group is ready, and the spells are cast, she slowly leads the group quietly into the entryway (Stealth: 23).

The music is an offbeat, horrible sounding, dischordant tune that might come from bone flutes. More than one are playing.

Daewen, you can see soft shadows of something begind the walls yes, but as you creepy and lead everyone, they do not attack, but continue to wail, and scream, and moan. It’s quite unnerving. If you were to attack whatever is behind the barrier, you could only use projectiles as all you can see along the walls are the arrow slits and no doors, just the one that leads deeper into the temple.

Carrhae is going to tap into the world of the spiritual and burn a use of Divine Sense to see if there are any undead in this chamber and that they might be the source of the screams. 

Nope

Carrhae frowns a bit after her senses don't pick up any undead. Oh goody. We're not dealing with the undead in this temple. Just people who are out of their minds. I guess that the Cult of the Howling Hatred had to earn their name somehow, right?

You enter a long dark hallway. One hallway leads north, another one leads south. Towards the east, you can see two doors, and the last hallway. The music is coming from door I mentioned in discord that's not on the map. (on the left 20' from where you exited)

Dark-one Daewen eventually leads the group through the Entryway of Death (TM), and successfully into the complex.  Upon hearing the horrid music get louder and louder from the doorway 20 feet down on the left, she motions for the rest of the group to stay there (in the entryway) while she invisibly takes a stroll through the door into the music room.

Stealth: 29

Daewen: A stone fountain stands in the middle of a grand plaza, its sides sculpted into the shapes of dwarves bearing drums and horns. Near the fountain, several figures in feathered attire play a shrill, discordant tune on flutes made of bone. They sound TERRIBLE. The lead performer who is playing seems very annoyed at how bad everyone else is.

"No, no, that's not right at all!" she whines.

Agreeing wholeheartedly with her 'that's not right at all' comment, Daewen withdraws from poking her head into the room, and silently closes the door.  Returning back to the group, she pantomimes the musicians playing their bone flutes, with the lead performer attempting to get the group under control...poorly.  Quickly drawing a diagram of the grand plaza in the dust on the ground, she outlines where the musicians were playing, as well as the fountain and the rest of the plaza.

She then looks to the group to decide where to move on to next...

Carrhae points down the hallway towards the south and then gives a thumbs up that lets Daewen know that the rest of them will be following behind her.

Zephyr kept their comments about the music to themselves despite their ears nearly bleeding, but once they found the source of the music, the changeling could not take it one last second and bust the door down into the room of where these baboons were practicing. They knew next to shit about music, but this sure as shit wasn't music and whether their friends came in or not was up to them, but Zephyr could not handle this any longer. 

"Oh my Traveler, you all sound absolutely horrendous!" Zephyr shouted, waving their hand in the air to get them to please stop the torture they were putting her poor ears through. "Please for all that is good and holy, just stop!" Once the "band" ceased their pain inducing music playing, Zephyr would address who would look to be the leader of the group. "Ma'am, can you please explain to me what you guys are trying to play here? Because all that ain't right. Maybe I or any of my party members could be of assistance."

"Yes!" The main performer says. "My sentiments exactly! You! Come!" She waves you over. "Tell me, how horrible do these initiates sound!! Can you play? Please tell me you can. I'm holding auditions! ANYONE would sound better than THESE miserable performers." The other performers/initiates look to the ground, ashamed. "Are you with others? I need GOOD musicians!"

Strife, somewhat astounded by this sudden and surprising turn of events, enters the room to join the others, and plays a small tune on her flute to warm up.

Performance (+7): 11

Mercy had grabbed at Zephyr's cloak to hold them back, missed and faceplanted into the floor. Standing up, she groaned in irritation and followed the rest into the room. Seeing the state of things (and wincing at the piercing sound of Strife's flute), she grabbed the instrument from her friend and looked it over. Finding the source of the problem, she pulled out her father's hunting knife and dislodge a small bit of dried vegetation that had somehow gotten lodged in the mouthpiece. "You should really be more careful how you store that thing, Vera." She handed it back to the bard with a long-suffering sigh and looked at the harried cultist with a look of commiseration. 

Carrhae notices Zephyr going down the hall to confront the lackluster musicians. Always on the move. Well, I can't let them go down without Bardic assistance. "Come on Strife, it sounds like these people need some help from the experts." While she's still covered in darkness, Carrhae will cast Disguise Self to make it look like she's wearing a dark purple dress with no back as well as dark blue eyeshadow on her face. Then she follows her fellow bard in. "My my, Veracity. I knew that these performers were atrocious, but they've got you so disoriented that you forgot which end of the flute to blow on. Oh, where are my manners? I'm Carin and this is my companion Veracity. We're traveling bards who came by looking to assist a dying animal and stumbled upon something much more sad. Clearly, you need some help before you cause someone to have permanent psychological damage. Here. I'm going to sing a few notes and you try to match them on your instruments."

Performance:22

"FINALLY!" Says the musical leader. "SOMEONE with some musical talent. Listen!" She waves to the initiates. "THAT is talent."

She glares at the initiates. "Get out of my sight." And they scurry away. Then she turns to Carrhae. "I like your style. I'm very impressed. Here. Welcome to the band. You friend needs a little..work. See to it!"

She hands you all initiate robes. "Meet me back here tomorrow night. We'll give them a performance they'll NEVER forget. Don't forget to practice!"

(You can now travel freely throughout the level.)