Sleep arh

My lil one WAS sleeping a average 5-6hour first stretch at night. Feeding and falling straight back to sleep. But...

We recently got a sound machine and I have been using the lullaby as part of our nap routine. Although she only takes short naps- this works well for putting her down and she is pretty good at knowing it’s nap time and soothing herself to sleep...

For night time however we cannot sleep while listening to the lullaby through the monitor so have put it on the typical white noise (which I believed was meant to help with sleep).

Now she is waking after just 3hrs and also staying awake for approximately an hour each time... I have tried letting her fuss and can hear her sucking her thumb to try soothe but she seems to take forever to fall back asleep and even with what appears to be a sleepy feed seems to stay awake for a while after... the noises keep me a hubby awake and I don’t know if I should quit the noise machine, give her more time to adjust or if it’s some weird stage she is starting to go through? And if so... what do I do? Hubby and I want our sleep back!