Which Captcha Service to use that can recognize capitals in the letters?

Hello Community,
I've been using DBC for about a year and pretty much satisfied, but I am in a search of the captcha recognition service that able to recognize capitals as well.

For example: If I load captcha with "rAVRc" to the deathbycaptcha it's gonna bring "ravrc" which is accurate but capitals are not recognized.
If anybody had previous experience with other captcha services that can bring this to the table, let me know,
Thanks