Device: iPhone 17 Pro Max iOS version: iOS 26.3 CarPlay type: Wired We are encountering two intermittent UI issues in CarPlay when running our music application. The problems occur occasionally and cannot be recovered without restarting the device. Issue 1: CPListImageRowItem image not displaying On the CarPlay home page, some images occasionally fail to appear. Implementation details: The list is updated using CPListTemplate.updateSections. Each item is a CPListImageRowItem. On iOS versions below 26, images are updated using updateImages. On iOS 26, images are provided through CPListImageRowItem.elements, where each element is a CPListImageRowItemRowElement. Observed behavior: Logs confirm that the data is correctly provided. However, in failing cases the CPListImageRowItemRowElement appears with both title and subtitle equal to nil. The image is not rendered in the UI even though the item exists. Issue 2: Now Playing bottom buttons occasionally missing On the Now Playing screen, the bottom control buttons sometimes fail to appear. Implementation details: Buttons are updated using CPNowPlayingTemplate.updateNowPlayingButtons. The buttons are instances of CPNowPlayingImageButton. Observed behavior: Occasionally the buttons are not displayed. Once this occurs, the UI does not recover. Restarting the phone immediately resolves the issue. Additional observations The issue appears to occur intermittently. Once triggered, it persists until the device is rebooted. Similar behavior has been observed in other music apps (for example, QQ Music). Questions Are there known CarPlay UI rendering issues related to CPListImageRowItem or CPNowPlayingTemplate in recent iOS versions? Is there any recommended workaround or lifecycle handling that might prevent these UI elements from failing to render? Any guidance would be greatly appreciated.

We're experiencing a severe main thread hang (29 seconds) in our CarPlay audio app when calling [CPListItem setImage:] on iOS 26.4. This issue affects 81% of our reported hang cases, and is concentrated on iOS 26.4. Environment iOS 26.4 CarPlay Audio app Images are downloaded via SDWebImage, resized to appropriate scale, then set via [CPListItem setImage:] on the main thread Problem When multiple list item images finish downloading around the same time, each setImage: call triggers expensive synchronous CoreUI operations on the main thread. The total accumulated time causes a 29-second freeze. The entire hang occurs inside Apple frameworks — no app code is on the hot path after calling setImage:. Call Stack (simplified) [CPListItem setImage:] └─ [CPImageSet initWithImage:treatmentBlock:] (57% + 21% + 18% = 96%) └─ [UIImageAsset imageWithTraitCollection:] └─ [UIImageAsset _withLock_imageWithConfiguration:] └─ [UIImageAsset _performLookUpRegisteredObjectForTraitCollection:] └─ [UITraitCollection _enumerateThemeAppearanceNamesForLookup:] └─ [CUICatalog _imageWithName:scaleFactor:deviceIdiom:...] └─ [CUIMutableStructuredThemeStore canGetRenditionWithKey:] └─ [CUIMutableStructuredThemeStore renditionWithKey:] └─ copyKeySignatureForKey / NSDictionaryM objectForKey: / CFStringCreateImmutableFunnel3 Code // Image download completion callback (dispatched to main queue by SDWebImage) if (finished && image) { UIImage *carPlayScaleImage = [UIImage imageWithCGImage:image.CGImage scale:[self getCarPlayDisplayScale] orientation:UIImageOrientationUp]; [item setImage:carPlayScaleImage]; // <-- hang here } Analysis Inside setImage:, the CarPlay framework creates a CPImageSet, which calls [UIImageAsset imageWithTraitCollection:] three times (at offsets +540, +344, +300 in CPImageSet initWithImage:treatmentBlock:). Each call performs a full CoreUI rendition key lookup via CUIMutableStructuredThemeStore, involving key signature computation, dictionary lookups, and string allocation. On iOS 26.4, these CoreUI operations appear significantly slower than previous iOS versions. When a CarPlay list loads ~20 items and images complete downloading in a short window, the serial execution of these setImage: calls on the main queue accumulates to a multi-second hang. Questions 1. Is this a known CoreUI performance regression in iOS 26.4? 2. Is there a recommended way to set images on CPListItem that avoids the heavy CPImageSet / UIImageAsset trait collection resolution path? 3. Are there any planned fixes for the CoreUI rendition lookup performance in upcoming iOS 26.x releases? Any guidance would be appreciated. We have also filed a Feedback report.