This has been happening since I bought the car in April. 2014 IS 350 AWD F Sport. At times my stereo seems like it is reduced by 25% or so of the volume and power. I get a phone call on the bluetooth and as soon as I hang up the stereo is nice and loud and full sounding again. The other day it happened again and it was a dramatic difference.

Doesn't matter if it is Pandora, a CD, radio etc. It is a very noticeable difference. Lexus enform and all other apps such as Pandora and slacker all all up to date. Phone volume I always check and make sure it is max. Any ideas guys?

 

i had a similar issue when streaming pandora (i dont really use cd or radio) with my samsung note 4. i had drastic volume differences after phone calls. i took the car back to the dealer and reinstalled the firmware with no luck. then they suggested i reformat my phone. it was pretty inconvenient , and i had to backup/reinstall everything on my phone, but everything worked great after i factory restored my phone.

but since your issue is with your cd and radio, i think it could be a firmware issue, but it probably wouldn't hurt to try reformatting your phone.

 

I have the same issue with Pandora