[DanKK87]

Hi guys, my friend just bought a Sennheiser RS170 wireless headset, on the case it stated that it can use up to 80m range, however my friend try it and it only can use up to 30m, he tried outside his house and there's nothing between the headset and the transmitter. Do anyone who got this RS170 and has the same issue? Thanks
 
*let me know if I post in the wrong place...