Several scenes where the mic and/or battery pack and wire between them showed clearly under Ryan's shirts.
At the end, when Josh holds the gun on Ryan, Josh says, "She was never good enough for you!" Unless he was trying to say that his opinion was that Ryan thought Vivian wasn't good enough for him, which was obviously never true, then he apparently got it backwards and meant to say, "You were never good enough for her!" - OR: "She's too good for you!" - something along those lines.