elevator noise into my condo unit (california)

[Guin Met]

California.

We live in a 2 bd condo in Woodland Hills, California which we purchased 2 years ago. We have had an issue with elevator noise coming in to our unit. Our unit is on the first floor and the engine room is below our bathroom.
Each time the elevator is active (we live in 100+ unit with 1 elevator) the noise comes into our unit. We are constantly woken up in the middle of the night, have trouble falling a sleep, and difficulties staying a sleep in the morning. It has created an unbearable living situation.

When we purchased the condo, we were one of the first ones to have moved into our building. (It is a 1200 unit apartment to condo conversion) We didn't hear the elevator noise until months after people began to move in.

Here is an audio of the sounds from my bedroom and also a video from the engine room:
1. Audio from bedroom (begins at 0:07) - Audio from Bedroom (Building 14 Unit 124) - YouTube
2. Audio/Video from engine room - Building 14 Elevator - Engine Room Noise - YouTube

We have addressed the problem to the HOA and have even had the elevator technician (contracted by the hoa) come out and assess the issue. He came into our unit and said the noise should not be coming into our unit and has proposed a suggestion. I have since then asked to view the proposal and the amount which they have refused for us to see. The amount is less than $1500.00 but it is not a guarantee according to the elevator technician.

They have since refused to correct the problem twice this year because the elevator was working and we were the only ones who have complained. We have no neighbors next to us and the people above us do not hear the noise from the engine room.

Because the HOA won't do anything, my next step is to go to the developers who sold us our unit but we are trying to find out if we even have any power to pursue this. (for example: undisclosed mechanical noise or owners easement of enjoyment)

Any advice would be greatly appreciated.
Thank you in advance.