We are currently experiencing an issue that occurs only on iPhone 17 models.
In our app, after connecting to an external device, users can download multiple video files stored on the device. When downloading several videos consecutively, the device consistently stops receiving responses midway through the process. As a result, no response is returned, and the connection between the app and the device is eventually lost.
This issue does not occur on any iPhone models prior to iPhone 17. It is reproducible across all iPhone 17 devices within our company.
This is a critical issue, and we need urgent assistance.
The main error logs show two patterns: • Connection loss • Timeout
At the OS level, the only error codes we receive are: • -1005 (Network connection lost) • -1001 (Request timed out)
Unfortunately, we are unable to obtain more detailed error information beyond these codes, which makes further debugging difficult.
We have attached the relevant logs below.
We would greatly appreciate any guidance on how to further investigate or resolve this issue.
310.0 / :: 81 % ::: 251.21481481481482
310.0 / :: 82 % ::: 254.23280423280423
310.0 / :: 83 % ::: 257.3820105820106
310.0 / :: 84 % ::: 260.4
KeepAlive SEND id=423F1336-6239-4B3B-9414-5A987D85D564 at=2026-02-24T12:56:43Z timeout=60.000000s
current: D20-Q2-PLUS, ssid: D20-Q2-PLUS_136a63
KeepAlive SKIP (in-flight)
tcp_output [C10.1.1:3] flags=[R.] seq=4017430266, ack=4146413113, win=2048 state=CLOSED rcv_nxt=4146413113, snd_una=4017429847
nw_read_request_report [C10] Receive failed with error "Operation timed out"
nw_flow_add_write_request [C10 192.168.000.0:443 failed parent-flow (satisfied (Path is satisfied), interface: en0[802.11], ipv4,
dns, uses wifi, LQM: good)] cannot accept write requests
nw_write_request_report [C10] Send failed with error "Socket is not connected"
Task <5BDBE621-329A-45E9-B236-9C173E92A41F>.<7> HTTP load failed, 361/0 bytes (error code: -1005 [4:-4])
Task <5BDBE621-329A-45E9-B236-9C173E92A41F>.<7> finished with error [-1005] Error Domain=NSURLErrorDomain Code=-1005 "The network
connection was lost." UserInfo={_kCFStreamErrorCodeKey=-4, NSUnderlyingError=0x13e632160 {Error Domain=kCFErrorDomainCFNetwork
Code=-1005 "(null)" UserInfo={NSErrorPeerAddressKey=<CFData 0x14cfe5a90 [0x201746068]>{length = 16, capacity = 16, bytes =
0x100201bbc0a86f010000000000000000}, _kCFStreamErrorCodeKey=-4, _kCFStreamErrorDomainKey=4}},
_NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <5BDBE621-329A-45E9-B236-9C173E92A41F>.<7>,
_NSURLErrorRelatedURLSessionTaskErrorKey=(
"LocalDataTask <5BDBE621-329A-45E9-B236-9C173E92A41F>.<7>"
), NSLocalizedDescription=The network connection was lost., NSErrorFailingURLStringKey=https://192.168.000.0/keepalive,
NSErrorFailingURLKey=https://192.168.000.0/keepalive, _kCFStreamErrorDomainKey=4}
KeepAlive FAIL id=423F1336-6239-4B3B-9414-5A987D85D564 elapsed=29.203s status=-1
error=Optional(Alamofire.AFError.sessionTaskFailed(error: Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost."
UserInfo={_kCFStreamErrorCodeKey=-4, NSUnderlyingError=0x13e632160 {Error Domain=kCFErrorDomainCFNetwork Code=-1005 "(null)"
UserInfo={NSErrorPeerAddressKey=<CFData 0x14cfe5a90 [0x201746068]>{length = 16, capacity = 16, bytes =
0x100201bbc0a86f010000000000000000}, _kCFStreamErrorCodeKey=-4, _kCFStreamErrorDomainKey=4}},
), NSLocalizedDescription=The network connection was lost.,
KeepAlive FAIL
1001 Log
KeepAlive SEND id=FC433405-C1F7-47EF-AF9E-D12E67B071FA at=2026-02-24T12:22:38Z timeout=60.000000s
current: D20-Q2-PLUS, ssid: VUEROID_D20-Q2-PLUS_136a63
KeepAlive FAIL id=FC433405-C1F7-47EF-AF9E-D12E67B071FA elapsed=7.834s status=-1
error=Optional(Alamofire.AFError.sessionTaskFailed(error: Error Domain=NSURLErrorDomain Code=-1001 "The request timed out."
UserInfo={_kCFStreamErrorCodeKey=60, NSUnderlyingError=0x135e612f0 {Error Domain=kCFErrorDomainCFNetwork Code=-1001 "(null)"
UserInfo={_NSURLErrorNWPathKey=satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, dns, uses wifi, LQM: good,
_kCFStreamErrorCodeKey=60, _kCFStreamErrorDomainKey=1}},
), NSLocalizedDescription=The request timed out.,
NSErrorFailingURLKey=https://192.168.000.0/keepalive, _kCFStreamErrorDomainKey=1}))
KeepAlive FAIL ignored count=1 error=Server error : Optional(Alamofire.AFError.sessionTaskFailed(error: Error Domain=NSURLErrorDomain
Code=-1001 "The request timed out." UserInfo={_kCFStreamErrorCodeKey=60,
KeepAlive SEND id=A64AE4C0-28B4-41E3-AAC9-422C41D99D15 at=2026-02-24T12:22:58Z timeout=60.000000s
KeepAlive FAIL id=110B96DA-4D88-45E0-B8F7-D0A9798593AE elapsed=43.605s status=-1
error=Optional(Alamofire.AFError.sessionTaskFailed(error: Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost."
UserInfo={_kCFStreamErrorCodeKey=-4, NSUnderlyingError=0x135e60f60 {Error Domain=kCFErrorDomainCFNetwork Code=-1005 "(null)"
UserInfo={NSErrorPeerAddressKey=<CFData 0x144dfee40 [0x201746068]>{length = 16, capacity = 16, bytes =
0x100201bbc0a86f010000000000000000}, _kCFStreamErrorCodeKey=-4, _kCFStreamErrorDomainKey=4}},
), NSLocalizedDescription=The network connection was lost., NSErrorFailingURLStringKey=https://192.168.000.0/keepalive,
NSErrorFailingURLKey=https://192.168.000.0/keepalive, _kCFStreamErrorDomainKey=4}))
KeepAlive FAIL ignored count=2 error=Server error : Optional(Alamofire.AFError.sessionTaskFailed(error: Error Domain=NSURLErrorDomain
Code=-1005 "The network connection was lost." UserInfo={_kCFStreamErrorCodeKey=-4, NSUnderlyingError=0x135e60f60 {Error
Domain=kCFErrorDomainCFNetwork Code=-1005 "(null)" UserInfo={NSErrorPeerAddressKey=<CFData 0x144dfee40 [0x201746068]>{length = 16,
capacity = 16, bytes = 0x100201bbc0a86f010000000000000000}, _kCFStreamErrorCodeKey=-4, _kCFStreamErrorDomainKey=4}},
Network type changed, hasWiFiInterface :false
We are sending a keepalive request every 30 seconds to maintain the connection state with the device. Most of the issues occur during this keepalive process, and this is when the logs mentioned earlier are generated.
Based on our debugging so far, the keepalive function itself is being called as expected. However, the execution appears to stall while waiting for a response from the device. After remaining in that state for some time, the session eventually ends with either a timeout or a connection loss error.
We are use almofire 4.0.1.
According to the firmware developer, when this issue occurs, there are no corresponding values or logs received on the device side.
Therefore, we are currently investigating whether this might be related to a networking issue on the iPhone side.
All other features are functioning normally. The problem occurs only when downloading VOD video files, and the reproduction rate is 100% under that condition.
At the OS level, the only error codes we receive are: … -1005 … -1001
Right. These are NSURLErrorNetworkConnectionLost and NSURLErrorTimedOut, respectively. They are transport errors, meaning that the HTTP request failed because something went wrong with the underlying TCP/IP transport connection (TCP for HTTP/2 and earlier, QUIC for HTTP/3). There’s more info about the -1005 error in QA1941 Handling “The network connection was lost” Errors. The -1001 is pretty straightforward: The transport connection stopped moving data and eventually the HTTP request timed out.
Given the above, you need to look for problems deeper in the TCP/IP stack. I usually start an investigation like this with an RVI packet trace, which lets you see what’s happening on the ‘wire’ as far as iOS’s TCP/IP stack is concerned.
I suspect you’ll find that the Wi-Fi has simply stopped delivering packets. The critical factor here is that it’s limited to iPhone 17 and friends. I’ve seen problems like that before. If you’re able to find enough evidence to convince yourself that this is a Wi-Fi level issue, I recommend that you file a bug, following the advice in this post.
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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"