You need to talk to your doctors about this ASAP.

From what I recall, it was (should still be) standard to get a hearing check for a baseline before starting certain chemo treatments, including cisplatin and carboplatin. (I had the carboplatin.) They do have a known side effect of hearing damage, and so you'll want to talk to your oncologists to let them know what you're experiencing, and decide as a team if the treatment is worth continuing or not, if your concerns are within the realm of normal or something beyond normal. Not something folks here could diagnose, even if we were any kind of medical professionals.

And ((hugs)) ! Halfway through rads is really good! Hang in there!