# Argh. Lost Comms with MCU is back **URL:** \ **Category:** General Discussion\ **Created:** [October 3, 2024, 5:59am UTC](https://klipper.discourse.group/t/argh-lost-comms-with-mcu-is-back/19183 "2024-10-03T05:59:29Z")\ **Posts on this page:** 1\ **Showing post:** 3
**Author:** ![dJOS\_500](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/djos_500/32/5001_2.png) [@dJOS\_500](https://klipper.discourse.group/u/dJOS_500)\ **Post date:** [October 3, 2024, 10:35am UTC](https://klipper.discourse.group/t/argh-lost-comms-with-mcu-is-back/19183/3 "2024-10-03T10:35:08Z")
Which version of the OS are you running? I found issues with the 64 bit versions of Pi OS and CanBus, and going to 32Bit made a huge difference. It might help with USB connected MCU’s too. > [@PSA: CanBus on 32 Bit vs 64 Bit Pi's - "Communication timeout" errors](https://klipper.discourse.group/t/psa-canbus-on-32-bit-vs-64-bit-pis-communication-timeout-errors/18336): > > G’day All, I ran into something in the last couple of days that doesn’t seem to be well documented - CanBus on 64 Bit Pi OS’s, eg Bullseye, is highly error-prone. My HW: SKR v2 → Pi 3B+ → U2C → EBB36 Context: I was running an old version of MainSali OS and needed to start a fresh OS build to update to the latest versions of Crowsnest and a couple of other extensions. So I thought I’d try starting with the 64 Bit version of MainSail OS 1.3.2. Anyway, after 2 days of constant “Communication tim… --- _[View the full topic](https://klipper.discourse.group/t/argh-lost-comms-with-mcu-is-back/19183)._