Hi everyone,

I'm trying to find out if anyone has experienced the same issue.

**TV**

* TCL 65Q6C (Google TV)
* Android 14
* Firmware V643 (also tested on V626 after downgrade by a TCL service technician)

# Problem

When watching movies with strong bass or loud action scenes, the **audio volume seems to "pump" or "pulse."**

It's not clipping or crackling.

The best way I can describe it is that the volume suddenly goes:

**Loud → quieter → loud → quieter**

almost like someone is rapidly adjusting the volume or like a compressor/limiter is overreacting.

It is especially noticeable during explosions, orchestral music, or scenes with heavy bass.

# Apps affected

* Apple TV (built-in Google TV app)
* Disney+

# Troubleshooting already done

* AI Sound ON/OFF
* Standard / Movie sound mode
* Dolby Atmos ON/OFF
* Auto Volume OFF
* DTS DRC OFF
* Factory reset
* Firmware downgraded from V643 to V626 by a TCL service technician

The issue still exists.

# Very important comparison

I purchased the **same movie** on a **KT set-top box (HDMI)** and played **the exact same scene**.

**Result:**

* Built-in Google TV Apple TV app → audio pumping
* korea KT set-top box (HDMI) → completely normal
* iPad Apple TV app → completely normal

So the movie itself is fine, and the TV speakers are capable of playing the same scene normally when the source is external.

# Service visit

A TCL service technician visited my home and watched a recorded video of the issue.

He said it **doesn't seem like a speaker hardware problem**, and downgraded the firmware to V626 for testing, but the issue remains.

# Question

Has anyone experienced something similar?

Could this be:

* Google TV audio framework?
* Dolby Digital Plus decoding?
* TCL audio DSP processing?
* A firmware bug?

If anyone has found a fix or had TCL replace the main board and solve the issue, I'd really appreciate hearing about it.

Thank you!

TCL Google TV - Audio volume "pumping" on built-in Apple TV & Disney+ apps (KT STB and iPad are normal)