I bought a cheap LEPY, not LEPAI, mini headphone amp to drive phones from the tv out. the out is set to FIXED. so the out and speakers are separately controlled. I am currently using a LINE LEVEL DRIVER, 15db gain with pots. issue is that "0" gain is not possible. I am hoping this simple analog amp will do the trick. I have no idea if the more expensive models are any more usable than this for $10.00. the line driver was slightly more and works well. even at the lowest setting the phones are too loud. without the driver they are barely driven, hence the amp. I can use the driver somewhere else. any opinions? i bought an inexpensive headphone amp. like most it uses an internal battery plus a micro usb charge port. comes with a usb cord to charge from any usb port, in my case the tv port. is this the same port a cell phone uses? if yes which brand uses that port style? i would rather use a 5 volt power supply to power the amp than simply charge the battery. what should I buy? what is the charge port standard? I took a chance on an unbranded/unmarked mini headphone amp. 1/8 stereo in/out with vol,charge port, gain control. included patch cords. charge light glows when connected to tv usb port. charging is independent of power switch. can use a cell phone ps with the proper connector, mini b?. no specs but the volume is too loud at 100%, exactly what I wanted so I could turn down to "0" if needed. the inline resister on my headphones are also at "0", no resistance. input comes from my tv. I am sure the input could be from anything. my LINE LEVEL DRIVER was 18db gain. the pots could not go down to "0", hence the replacement. I also bought a cheap generic mini amp for headphone and speakers. probably a common connection. a switch could be added to each output I suppose. although I know nothing about this little black box it works for me. it could probably drive small un powered speakers. maybe even powered speakers. the advantage there would be three volumes, one at the amp. one at each speaker, or a common one for both. in any event works well as designed. in my opinion it is worth a try for others.