Nari Ultimate and PS4 Pro Battery Life

Howdy. I recently bought a Nari Ultimate headset for use with my PS4 Pro and after charging it initially for over 8 hours (the charging light turned green at a little over 4 hours), I'm not seeing the expected battery life from the headset. Based on advertisements and user experience, I was expecting to see 6 or more hours of continuous use with haptics enabled before the headset required charging.

On average, I'm getting about 3-4 hours before the headset begins warning me that the battery is low and I have to plug it in to charge.

I'm using the headset wirelessly with the provided dongle and I've charged it using multiple cables including the one provided and multiple charge sources (I have several powered hubs that provide the full 5V at 2A for device charging).

I have installed Synapse 3 on a Windows based PC and connected the device to it but I'm unable to get Synapse to indicate that there is a device connected by either plugging the dongle into the machine or plugging in the USB cable and as a result am unable to try things like turning off the haptics while charging as suggested by other posters.

The big question here is whether my experience so far is as expected or is the device likely needing replacement/repair? It was brand new in an unopened box when purchased from Best Buy about a month ago.

Thanks in advance for the help.