inputs.text: teli usba6rf unstable must modified function minimal level - 12 volt amplifier mp3 player usb sd fm smallest size amplifier type encountered fm wire antenna amplifier unusual player not rehemehember digital volume control setting rendering digital volume setting basically useless since must reset every time power rehemoved digital volume 30 steps player rehemehembers track played player rear mounted power switch unit channels reversed input output amplifier inverting compensated speakers connectedthis player high frequency oscillation output beginning well one watt output indicating instability amplifier reset dc volume control amplifier ic lower gain get rid oscillation requires disassehembly modification amplifier even change output clips 1 watt peak peak 4 ohms 62 milliwatts rms 8 ohms change frequency response ok 60 hz bass maximum treble minimumunless handy diagnosis repair electronic equipment would give unit pass since appears severe design problehems consisting amplifier instability oscillation signal clipping beginning 65 milliwatts rms 8 ohms modification amplifier function limited power headphone amplifier limited low frequency response disappointing high quality headphones since good low frequency response required serious computer gamers amplifier disappointingsimilar products made lepai a6 usb a68 similar products without fm made kentiger hy501 veikor cheng sheng hs9004 similar products display fm made kentiger hy502 lepai lpa7usb kinter ma120 one least problehems box kentiger hy502 see individual reviews itehems details personal favorite kentiger hy501 added mp3 power supply filtering hy501 available without fm section