Dealer wants 2400 for new amp. Told them to take a hike

[PureH8]

Hey Guys

A little about my car, 2006 530xi logic 7 sound system. No nav. COP car. Love the car, hate how often it needs to go to the shop. 8 hr round trip to dealer from my house. WTF

Problem....

My music, blue tooth audio, PDC audio is not working. I have lost all speakers except the subs. I have control of the functions from idrive, (read that it matters???) I took it into the dealers and they told me it was the amp, they want $2400 just for the amp. Told them to take a hike.
Now after searching around a bit tonight I have found out this so far
1. Very hard to find a repair shop for the amp
2. Fiber optic makes no aftermarket options???
3. Not many used ones out here were I live
4. Dealer says they need to program it???? Not plug and play????
5. Thinking I should not have told dealer to take a hike. Lol

Any ideas? solutions?

Thanks guys for your comments and help in advance