Last year, my friend replaced the original left rear strut and changed to Monroe OESpectrum, but reused original spring. Also replaced mount. Ever since, it (most of the time, but not always) will make a single pop sound when coming to a stop, and also a single pop when accelerating from stopped position. Always just a single pop sound. No other noises, no noise when turning. I have searched a lot online for this, but seems most people have different noises or only when turning. Any ideas what could be causing this? Thanks.