- Dec 21, 2014
Just purchased the Hifiman ef-5 hybrid amp, noticed after about a 10 minute warm up, when I plugged in my source (iphone6 connected via USB to headphone jack) that there was a slight low buzz that occasionally turned into a slightly higher volume tick-tick-tick, and then back to the low buzz( low buzz could have been there all along, but the tick was more obvious. What do y'all think this could be? Amp is new and so is tube. I am using an older RCA to headphone jack cable. Of course plugged into wall. Any ideas are appreciated.