I have also found ER4P, ER4S and HF5 all have microphonics. HF5 is slightly better than the ER4 series, but still ranks pretty high compared to other IEMs I've tried (Senn IE8, IE7, UM3x, W3..etc). Running them over the ears would 'fix' microphonics for the most part, but it may be harder to do on HF5 (I've sold it off already) due to the angle of earpiece cable. ER4 is nearly impossible to wear over the ears with the original cables.
6/1/09 at 12:02pm