Sound problems in 5th generation iPod. Bad Battery?

I have a fifth generation ipod, and sometimes the sound does not play. Electrical noise is heard at times. All other functions work, games, calendar, information on-screen playback ...

The service technician tells me that the problem is the battery. But I notice that the capacity is almost the same as when new.

My question is: can a bad battery cause these problems of noise and silence?

Thanks and sorry for my bad english.