How to connect Thresher Ultimate (PS4) to PS4 Slim?

The headset is not designed for PS4 Slim so you'll have to jerry-rig a workaround. You can try this if your TV has an optical out:

• Connect the optical cable from the base station to the optical output of the TV.
• Connect the USB cable from the base station to one of the USB ports on the front of the PS4 Slim.
• Turn on the headset and the wireless transmitter, then activate the surround sound through the dedicated button located on the base station.
• The PS4 Slim should switch to headset audio. If it doesn't, you'll have to check the sound output settings on the display and sound settings.

Thanks for your reply Caziel. It was helpful. Sorry for not replying sooner. Yes my smart TV has an optical output port so I was able to connect as suggested. Just a little background. I have a sound bar that was connected directly to the TV's optical port. So what I did in order to also connect the base station's optical cable to it I attached an optical hub (1 male to 2 female) to the TV's optical. Then it was just a matter to connect the sound bar's optical cable to one end/port and the base station's optical cable to the other hub's available female port. So that took care of both being connected. What made the difference to the chat audio being clearer in and out was turning on the surround sound on the headphone's base station. Everything works fine now. Just wanted to outline what I did in case anyone else also has a sound bar connected to TV in case may be helpful. Cheers.

I am pleased to hear that it all worked out for you and I appreciate you updating the thread. I'm sure it will help others in the future. In order to preserve this, I'll be locking the thread as resolved.