With headphones using a digital audio wireless audio transmission a you may experience a short delay in the audio. This is known as latency.
Latency refers to a short period of delay (usually measured in milliseconds) between when an audio signal enters and when it emerges from an electronic device. Potential contributors to latency in an audio system include analogue-to-digital conversion, buffering, digital signal processing, transmission time, digital-to-analogue conversion and the speed of sound in air.
As the RS 160/170/180 systems use digital transmission technology, the audio will be subject to all of the above effects, as opposed to the RS 110/120/130/140 all of which use analogue transmission technology which only has a very small latency time of around 1 to 2ms.
Unfortunately nothing can be done to reduce the effects of latency of digital transmission technology.
You may like to try the newer RS 165, 175 or 185 headphones, which have a slightly reduced latency, though there is still some latency effect with these models.