[tbaig]

I recently installed the Bimmertech amp and I noticed a difference between the sound output depending on the source. When I play music from Bluetooth, the sound is very low. When I play from a USB source, specifically Spotify, the audio is louder but not as loud as when I use the native Music app on my phone and play music I've downloaded.
With Spotify, I've downloaded the music in 320 kbps. Even when I play music on the radio it's much louder than Bluetooth audio or USB Spotify.

Has anyone encountered this issue?

I am using an iPhone X btw.

[K8_M235i]

I usually listen to either Xm radio or Spotify over Bluetooth on an iPhone X

From my experience quality goes:

Phone with USB>phone with Bluetooth> Xm=fm radio.

Volume is definitely loudest on the Xm and fm radio, but I don't find the volume lacking when playing music from my phone. The dial just needs to be turned up a bit stronger to achieve the same listening volume.

I don't think there's an issue because I've had the same experience in every other car I've had with usb/Bluetooth capabilities.

[tbaig]

Any reasons why there is such discrepancy? When i use the Music app, the sound system sounds great but when I play downloaded music from Spotify it doesn't bump, even when i put the volume higher.

[Viffermike]

Read this thread, particularly starting at post #10. It explains why most of what you're describing happens.

There is no fix thanks to the 2 Series HU's lack of source-gain adjustment, but there may be a workaround through the Audiotec Fischer DSP software if you use the Bimmertech amp's digital input. That said, it would not allow for on-the-fly gain adjustment of that input unless you invested in a wired remote for the Bimmertech.

[tbaig]

What's the workaround? I do have the auditech amp and access to the software.

[Viffermike]

Originally Posted by tbaig

What's the workaround? I do have the auditech amp and access to the software.

Adjusting the gain for the digital input of the amp (via the software) to match the gain from the master volume of the HU.

The main problems with that are twofold:
- It might only work for one source plugged into the digital input. If you plugged another source into the input, the amp my have the same issues with input gain that the HU does.
- You would need to plug the source into the amp, which means running a wire from the back of the car to the cabin.

I believe the Bimmertech amp (which is actually a Match PP86DSP) has an optional wired remote that has a source-input gain adjustability function. It is not cheap, however, IIRC.

[Questofthetune]

Side note to streaming Spotify- did anyone else running a regular headunit with BT codes in after, have one glorious week where steering wheel dial worked to change songs and then it was gone again forever?