PEER

4.2.2 Changes - PEER 4.2 introduced a regression where some recordings were shown as recorded at 500Hz when they were actually recorded at 250Hz. While PEER 4.2.1 corrected the underlying sample rate error, recordings made with PEER 4.2 displayed the incorrect 500Hz sample rate. PEER 4.2.2 corrects this error so that all recordings display their correct sample rate in the recording detail view. There is no impact on the underlying EEG data or marker placement. This fix also addresses related problems with exports (BrainVision and PEER Archive), ERP analyses, quality analysis, and EEG chart timebases. - Resolved a problem where PEER incorrectly recorded dropped samples when exiting the Signal Quality view. This view appears before each block of a game and in the Settings panel while an X.on is connected. PEER tracks lost samples using a counter the X.on sends with each block of data. Every time the Signal Quality view appears, PEER takes the headset in and out of impedance mode, and the headset restarts that counter. PEER was reading the restart as roughly 65,000 lost samples. This is why affected recordings reported dropped samples when in fact there was no lost data. For existing recordings made with PEER 4.2 and 4.2.1, you can ignore the displayed lost sample percentages. The EEG recorded during the trials is intact. In each affected recording, one of these events wrote many seconds of empty samples into the file, between two blocks rather than inside one. In a BrainVision export, this shows up as a stretch of zeros across all channels. Marker positions are unaffected, so epoching around the block markers works as it should. To find the gap, look for a long run of exact zeros between two block start markers. - BrainVision export now writes the correct sample rate for recordings made with PEER 4.2 that were incorrectly shown as 500Hz. Re-export any previously exported recordings to correct the sample rate. - The dropped samples percentage shown for a recording now excludes samples dropped during the Signal Quality view. - Improved the Signal Quality view to show ground and reference impedance. - Improved the Signal Quality view to prevent false displays of the “No reference signal” warning. - Resolved a problem where importing a PEER Archive set the recording’s build number to that of the version of PEER doing the import. Imported recordings now keep the build number of the version of PEER that made the recording. - The signal quality display in the Settings panel, shown while connected to an X.on, now matches the Signal Quality view, including ground and reference impedance. - The Bluetooth UUID is no longer shown in the EEG headbands list. - Addressed a problem where the Select All/None, Share and Delete bottom toolbar buttons are missing when the Recordings View is in edit mode. This problem arises on iOS 26 and later. PEER 4.2.1 Changes - Resolved a problem where null EEG data was recorded during baseline recordings. - Resolved a problem where X.on game recordings contained 250Hz data despite the application indicating the recordings contained 500Hz data. This problem did not affect raw EEG recordings. The problem occurred when PEER’s Signal Quality view placed the X.on in Impedance mode, where the X.on switches to a 250Hz sample rate. When the Signal Quality view was dismissed, PEER returned the device to EEG mode but failed to switch it back to 500Hz. - Improved impedance displays in the Signal Quality view. - Improved detail view appearance under iOS Liquid Glass (iOS 26 and later). - Internal code cleanup.