# Ping2 Sonar 0% confidence **URL:** \ **Category:** Ping Viewer\ **Created:** [May 7, 2024, 5:40pm UTC](https://discuss.bluerobotics.com/t/ping2-sonar-0-confidence/16818 "2024-05-07T17:40:51Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![HasanTheSyrian](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/hasanthesyrian/32/11451_2.png) [@HasanTheSyrian](https://discuss.bluerobotics.com/u/HasanTheSyrian)\ **Post date:** [May 7, 2024, 5:40pm UTC](https://discuss.bluerobotics.com/t/ping2-sonar-0-confidence/16818/1 "2024-05-07T17:40:51Z")
Hello, I’m trying to test the Ping2 Sonar but it’s giving me inaccurate results and 0% confidence, am I supposed to use it underwater? I don’t have access to a pool right now and our AUV is incomplete. Can I test it in my bathtub, its \>0.3m. Thanks in advance. ---
**Author:** ![HasanTheSyrian](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/hasanthesyrian/32/11451_2.png) [@HasanTheSyrian](https://discuss.bluerobotics.com/u/HasanTheSyrian)\ **Post date:** [May 7, 2024, 5:58pm UTC](https://discuss.bluerobotics.com/t/ping2-sonar-0-confidence/16818/2 "2024-05-07T17:58:00Z")
Here it says I can use it in air with a certain speed of sound, but when I try to change the speed in the app it resets to 1500 m/s. [https://docs.bluerobotics.com/ping-viewer/device-settings-ping1d/](https://docs.bluerobotics.com/ping-viewer/device-settings-ping1d/) update: speed of sound can be changed with debug mode on ---
**Author:** ![tony-white](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/tony-white/32/13297_2.png) [@tony-white](https://discuss.bluerobotics.com/u/tony-white)\ **Post date:** [May 8, 2024, 2:34am UTC](https://discuss.bluerobotics.com/t/ping2-sonar-0-confidence/16818/3 "2024-05-08T02:34:36Z")
Hi @HasanTheSyrian - You should be able to test the unit in your bathtub, but may not get great results. A 5 gallon bucket can serve as well, but I wouldn’t expect 100% confidence or an accurate measurement!