Weird problem with wireless signal

Hello. I hope someone could help me!

Basically, my mum and dad purchased an iMac 3-4 months ago. The network setup is as follows.

Virgin Media > Netgear Wireless Router > Wired PS3
.......................................................> Wireless connection to iMac

(Note, this also applies when the PS3 is turned off)

The iMac has full signal, use the internet and lovely fast speeds, then, it drops to 1 bar, or even none... Then, all of a sudden, it jumps to full again.

Have noticed this more when I dowload a large file, it jumps from full to 1/none.

They have a windows laptop which is perfect, full signal and does not drop. So, im guessing it has something to do with the iMac.


Anyone have any ideas?!

Thank you

 

Not even 1 reply ?