it should be on pretty loud - is it the babysooth one? - if so we use it too!! I have just checked the level on our cd playes and it says -22dB if that helps!! We used it for our DD to help her get to sleep on her own and now use it for my son also. With regard to when to play it, if it is babysooth it runs for about 25 mins - that was enough to put my daughter to sleep. With my son, he seems to require it on all the time as when it stops he wakes up automatically so we have it on repeat for him and he wakes at the next feed cycle. We also found it worked well at pushing out 5am wake ups to more civilised 7am ones!!
My daughter grew out of it (ie it didn't work anymore!!) at the age fo 7 months and I was gutted but it lasted us well and helped her learn to slepp independantly without dummy rocking etc. I have ot say I still had some issues with 45 minute naps but that may be because we didn't have it on all the time or go in before the "jolt" stage so by the time I went in she was already wide awake!!
My son is only 8 weeks old so we're still experimenting what works best for him - though hes not as susceptible to it as she was :roll: .
Good Luck and I hope it works out!!
Clare
Mum to anna 23months and nathan 8 weeks