So stupid. Tried multiple things, fresh batteries, different ports, different modes, diy vids, etc etc etc etc. It did not seem to noticeably drain my phone battery any more than using normal headphones. Overall, the design (while an older model) is very similar to the M-100’s with a few exceptions:(1) The wireless Crossfades don’t fold up into the ultra compact case which I did like but wasn’t about to spend more than double for that feature. I found that they ran a little short and had to go up 1/2 a size but that was not a problem. I also happen to be very rough-handed with my buds so it was probably a fault on my end. So, I would say the sizing runs a tad small but I get confused with all the different sizing. For calls, you need to be in a quiet area, otherwise the other person cant understand a thing. And when I compared both shoes to other 6 toddler shoes that my daughter has, including a pair of boots, the other new pair was similar but this one was way bigger than all! Aha!