Help! Source Output Too High for Headphones

I'm looking for any suggestions on how to reduce the output from my source, a Sony XA5400ES CD player. 

I run the CD player to my headphone amp, either a iFi Pro ican, or a Woo WA22 amp. With any of my headphones 

which are high or low efficiency, high or low impedance, I can only turn the volume up 1 or 2 notches, or below 9 o'clock.

There is no volume adjustment on the Sony, unlike my Oppo 105D. 

Can I put anything in-line to reduce the output?

Just thought I'd follow up. I received XLR attenuators for my balanced output, and Schiit SYS for the unbalanced output. Both work great and kept me from buying a preamp.

Thanks for the suggestions!
Yes, there are many products that can cut the volume. Excessive loudness was a common problem with older airplane headphone jacks. I bought a $10 Koss product 1 a long time ago for air travel alone (it’s pretty flimsy and just okay IMO).
With a quality full-size CD player, I’m guessing you’d want something more substantial. There are plenty of simple desktop volume controls of varying quality (example 2), and more complex pro audio items too (which typically use 1/4" or XLR cables; example 2). Beyond this, you could buy a passive or active preamp 1 with volume, balance, tone, source selectors, etc.