The best test is to check the level of your iPod on headphones and take those phones with you to a retailer with a decent range of MP3 players.
Personally, having owned an iPod I'm now a fan of the Sony range -- cheaper than Apple, notably good sound quality and (above all) drag and drop loading -- none of the restrictions of vile iTunes.
Thanks for you suggestion. I rarely use the Ipod with headphones. I am using the Ipod as music source on a motorcycle. Again, I can not find the actual audio output of the Ipod Nano 8gig but have been told the Iphone has a much greater audio output. So I am trying to find an Ipod like device/MP3 player with a much stronger audio output to use on the motorcycle. Hope this makes sense?!!!