New to digital audio

Ipod? You fecking serious?

at the same time here, Bob, do some Research yourself.

or, do what most do and buy a Bluesound Node 2i.
it does BT, AirPlay, or uses its own I think.
also, a key part of streaming is the control app.
then get a trial account for Tidal.

but, enough with the “I don’t really know what a streamer is” BS...seriously.

if you don’t know that and have not taken the time to fine out, then you deserve to be confused.....sorry.

I'm using the IPOD because it is what I owned when I put this system together last year. I know it's not a great source so now I am trying to figure out how to replace it in my system and find what's the best way to listen to my music. 
I'll make sure to use a direct connection .
I have a PC for a laptop.
Like I said initially above - I've done lots of reading about this but for this 70 year old retiree technology can be very confusing. 
Hadn't considered Tidal or any other service like that because I'm happy with all the music I own.
This system is in our winter home in FL - my cd collection in NH is too big to take back and forth so looking for the best way to listen to my cd's
 

You don’t have to replace the iPod. Bluetooth is ok but you can improve the sound quality with WiFi or a direct connection. How does your current setup sound to you? If it sounds ok, than keep using Bluetooth. Some people are perfectly fine with it.

I would try to find another DAC/preamp. I would suggest an Emotiva XDA-2 or Emotiva Stelth DC-1. These have loseless volume controls unlike the XDA-1 which is lossy (sound quality decreases as you lower the volume). 

You could also get a stand alone preamp and just use the XDA-1 as a DAC. In this case, you set the volume on the XDA-1 to maximum and just use the volume control on the preamp.