About 90% of the time, when I'm on the phone and I get another line my conversation with first caller is instantly muted both ways. If I reject the new call then I am able to continue my conversation with the first call. If I hit accept I can talk to the second caller but since I was unable to tell the first caller that I have another line he hangs up and calls me back which now mutes my conversation again. Very aggravating! I called Sprint several times and no one had heard of this issue. They blamed the apps and suggested I do a hard reset on the phone. I also tried Google but found nothing. Anyone else experience this??