I have a laptop (Acer Aspire 5670) which is connected to a set of 2.1 speakers via the only possible connection (which is a black SPDIF port) but there is a strange recurring beeping sound which I can hear. It's difficult to describe so I did my best too record it (listen to it loud and you can hear it) It's really annoying, especially with headphones on. Can anyone help me to get rid of it? Do I just need a new soundcard? Thanks in advance.